• Connection String Options

Connection String OptionsBack To Top

1. AuthScheme
2. Server
3. Port
4. User
5. Password
6. Database
7. UseSSL
8. AuthDatabase
9. ReplicaSet
10. DNSServer
11. KerberosKDC
12. KerberosRealm
13. KerberosSPN
14. KerberosKeytabFile
15. KerberosServiceRealm
16. KerberosServiceKDC
17. KerberosTicketCache
18. SSLClientCert
19. SSLClientCertType
20. SSLClientCertPassword
21. SSLClientCertSubject
22. SSLServerCert
23. SSHAuthMode
24. SSHClientCert
25. SSHClientCertPassword
26. SSHClientCertSubject
27. SSHClientCertType
28. SSHServer
29. SSHPort
30. SSHUser
31. SSHPassword
32. SSHServerFingerprint
33. UseSSH
34. FirewallType
35. FirewallServer
36. FirewallPort
37. FirewallUser
38. FirewallPassword
39. Logfile
40. Verbosity
41. LogModules
42. MaxLogFileSize
43. MaxLogFileCount
44. Location
45. BrowsableSchemas
46. Tables
47. Views
48. AutoCache
49. CacheDriver
50. CacheConnection
51. CacheLocation
52. CacheTolerance
53. Offline
54. CacheMetadata
55. BatchSize
56. ConnectionLifeTime
57. ConnectOnOpen
58. DataModel
59. FlattenArrays
60. FlattenObjects
61. GenerateSchemaFiles
62. MaxRows
63. NoCursorTimeout
64. Other
65. Pagesize
66. PoolIdleTimeout
67. PoolMaxSize
68. PoolMinSize
69. PoolWaitTime
70. PseudoColumns
71. QueryPassthrough
72. Readonly
73. ReadPreference
74. RowScanDepth
75. RTK
76. SlaveOK
77. SupportEnhancedSQL
78. Timeout
79. TypeDetectionScheme
80. UseConnectionPooling
81. UseFindAPI
82. WriteConcern
83. WriteConcernJournaled
84. WriteConcernTimeout
85. WriteScheme

AuthScheme

Data Type

string

Default Value

"NONE"

Remarks

Accepted values are MONGODB-CR, SCRAM-SHA-1, SCRAM-SHA-256, GSSAPI, PLAIN, and NONE. The following authentication types correspond to the authentication values.

Authenticating with Challenge-Response

Generally, this property does not need to be set for this authentication type, as the driver uses different challenge-response mechanisms by default to authenticate a user to different versions of MongoDB.

• MongoDB 2: MongoDB 2 uses MONGODB-CR to authenticate.
• MongoDB 3.x: MongoDB 3 uses SCRAM-SHA-1 by default; new users you create in MongoDB 3 use this authentication method. However, MongoDB 3 servers will continue to use MONGODB-CR to authenticate users created in MongoDB 2.6.
• MongoDB 4.x: MongoDB 4 uses SCRAM-SHA-1 by default and does not support the deprecated MongoDB MONGODB-CR authentication mechanism.

Authenticating with LDAP

Set AuthScheme to PLAIN to use LDAP authentication. This value specifies the SASL PLAIN mechanism; note that this mechanism transmits credentials over plain-text, so it is not suitable for use without TLS/SSL on untrusted networks.

Authenticating with Kerberos

Set AuthScheme to GSSAPI to use Kerberos authentication. Additionally configure the following properties as configured for the MongoDB environment:

KerberosKDC	The FQDN of the domain controller.
KerberosRealm	The Kerberos Realm (for Windows this will be the AD domain).
KerberosSPN	The assigned service principle name for the user.
AuthDatabase	This value should be set to '$external'.
User	The user created in the $external database.
Password	The corresponding User's password.

Authenticating with X.509 Authentication

Set AuthScheme to X509 to use X.509 certificate authentication.

Server

Data Type

string

Default Value

""

Remarks

The host name or IP address of the server hosting the MongoDB database. If you choose to connect using DNS seed lists, set this option to "mongodb+srv://" + the name of the server your MongoDB instance is running on..

Port

Data Type

string

Default Value

"27017"

Remarks

The port for the MongoDB database.

User

Data Type

string

Default Value

""

Remarks

Together with Password, this field is used to authenticate against the MongoDB server.

Password

Data Type

string

Default Value

""

Remarks

The User and Password are together used to authenticate with the server.

Database

Data Type

string

Default Value

""

Remarks

The name of the MongoDB database.

UseSSL

Data Type

bool

Default Value

false

Remarks

This field sets whether the driver will attempt to negotiate TLS/SSL connections to the server. By default, the driver checks the server's certificate against the system's trusted certificate store. To specify another certificate, set SSLServerCert.

AuthDatabase

Data Type

string

Default Value

""

Remarks

The name of the MongoDB database for authentication. Only needed if the authentication database is different from the database to retrieve data from.

ReplicaSet

Data Type

string

Default Value

""

Remarks

This property allows you to specify the other servers in the replica set in addition to the one configured in Server and Port. You must specify all servers in the replica set using ReplicaSet, Server, and Port.

Specify both a server name and port in ReplicaSet; separate servers with a comma. For example:

Server=localhost;Port=27017;ReplicaSet=localhost:27018,localhost:27019;

To find the primary server, the driver queries the servers in ReplicaSet and the server specified by Server and Port.

Note that only the primary server in a replica set is writable. Secondaries can be readable if the SlaveOK setting allows it. To configure a strategy executing SELECT queries to secondaries, see ReadPreference.

DNSServer

Data Type

string

Default Value

""

Remarks

Specify the DNS server when resolving MongoDB seed list.

KerberosKDC

Data Type

string

Default Value

""

Remarks

The Kerberos properties are used when using SPNEGO or Windows Authentication. The driver will request session tickets and temporary session keys from the Kerberos KDC service. The Kerberos KDC service is conventionally colocated with the domain controller.

If Kerberos KDC is not specified, the driver will attempt to detect these properties automatically from the following locations:

• KRB5 Config File (krb5.ini/krb5.conf): If the KRB5_CONFIG environment variable is set and the file exists, the driver will obtain the KDC from the specified file. Otherwise it will attempt to read from the default MIT location based on the OS: C:\ProgramData\MIT\Kerberos5\krb5.ini (Windows) or /etc/krb5.conf (Linux)
• Java System Properties: Using the system properties java.security.krb5.realm and java.security.krb5.kdc.
• Domain Name and Host: The driver will infer the Kerberos Realm and Kerberos KDC from the configured domain name and host as a last resort.

Note: Windows authentication is supported in JRE 1.6 and above only.

KerberosRealm

Data Type

string

Default Value

""

Remarks

The Kerberos properties are used when using SPNEGO or Windows Authentication. The Kerberos Realm is used to authenticate the user with the Kerberos Key Distribution Service (KDC). The Kerberos Realm can be configured by an administrator to be any string, but conventionally it is based on the domain name.

If Kerberos Realm is not specified the driver will attempt to detect these properties automatically from the following locations:

• KRB5 Config File (krb5.ini/krb5.conf): If the KRB5_CONFIG environment variable is set and the file exists, the driver will obtain the default realm from the specified file. Otherwise it will attempt to read from the default MIT location based on the OS: C:\ProgramData\MIT\Kerberos5\krb5.ini (Windows) or /etc/krb5.conf (Linux)
• Java System Properties: Using the system properties java.security.krb5.realm and java.security.krb5.kdc.
• Domain Name and Host: The driver will infer the Kerberos Realm and Kerberos KDC from the user-configured domain name and host as a last resort. This might work in some Windows environments.

Note: Kerberos-based authentication is supported in JRE 1.6 and above only.

KerberosSPN

Data Type

string

Default Value

""

Remarks

If the SPN on the Kerberos Domain Controller is not the same as the URL that you are authenticating to, use this property to set the SPN.

KerberosKeytabFile

Data Type

string

Default Value

""

Remarks

The Keytab file containing your pairs of Kerberos principals and encrypted keys.

KerberosServiceRealm

Data Type

string

Default Value

""

Remarks

The KerberosServiceRealm is the specify the service Kerberos realm when using cross-realm Kerberos authentication.

In most cases, a single realm and KDC machine are used to perform the Kerberos authentication and this property is not required.

This property is available for complex setups where a different realm and KDC machine are used to obtain an authentication ticket (AS request) and a service ticket (TGS request).

KerberosServiceKDC

Data Type

string

Default Value

""

Remarks

The KerberosServiceKDC is used to specify the service Kerberos KDC when using cross-realm Kerberos authentication.

In most cases, a single realm and KDC machine are used to perform the Kerberos authentication and this property is not required.

This property is available for complex setups where a different realm and KDC machine are used to obtain an authentication ticket (AS request) and a service ticket (TGS request).

KerberosTicketCache

Data Type

string

Default Value

""

Remarks

This property can be set if you wish to use a credential cache file that was created using the MIT Kerberos Ticket Manager or kinit command.

SSLClientCert

Data Type

string

Default Value

""

Remarks

The name of the certificate store for the client certificate.

The SSLClientCertType field specifies the type of the certificate store specified by SSLClientCert. If the store is password protected, specify the password in SSLClientCertPassword.

SSLClientCert is used in conjunction with the SSLClientCertSubject field in order to specify client certificates. If SSLClientCert has a value, and SSLClientCertSubject is set, a search for a certificate is initiated. See SSLClientCertSubject for more information.

Designations of certificate stores are platform-dependent.

The following are designations of the most common User and Machine certificate stores in Windows:

MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.
SPC	Software publisher certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (for example, PKCS12 certificate store).

SSLClientCertType

Data Type

string

Default Value

"USER"

Remarks

This property can take one of the following values:

USER - default	For Windows, this specifies that the certificate store is a certificate store owned by the current user. Note that this store type is not available in Java.
MACHINE	For Windows, this specifies that the certificate store is a machine store. Note that this store type is not available in Java.
PFXFILE	The certificate store is the name of a PFX (PKCS12) file containing certificates.
PFXBLOB	The certificate store is a string (base-64-encoded) representing a certificate store in PFX (PKCS12) format.
JKSFILE	The certificate store is the name of a Java key store (JKS) file containing certificates. Note that this store type is only available in Java.
JKSBLOB	The certificate store is a string (base-64-encoded) representing a certificate store in JKS format. Note that this store type is only available in Java.
PEMKEY_FILE	The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
PEMKEY_BLOB	The certificate store is a string (base64-encoded) that contains a private key and an optional certificate.
PUBLIC_KEY_FILE	The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
PUBLIC_KEY_BLOB	The certificate store is a string (base-64-encoded) that contains a PEM- or DER-encoded public key certificate.
SSHPUBLIC_KEY_FILE	The certificate store is the name of a file that contains an SSH-style public key.
SSHPUBLIC_KEY_BLOB	The certificate store is a string (base-64-encoded) that contains an SSH-style public key.
P7BFILE	The certificate store is the name of a PKCS7 file containing certificates.
PPKFILE	The certificate store is the name of a file that contains a PuTTY Private Key (PPK).
XMLFILE	The certificate store is the name of a file that contains a certificate in XML format.
XMLBLOB	The certificate store is a string that contains a certificate in XML format.

SSLClientCertPassword

Data Type

string

Default Value

""

Remarks

If the certificate store is of a type that requires a password, this property is used to specify that password to open the certificate store.

SSLClientCertSubject

Data Type

string

Default Value

"*"

Remarks

When loading a certificate the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property. If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks the first certificate in the certificate store.

The certificate subject is a comma separated list of distinguished name fields and values. For example, "CN=www.server.com, OU=test, C=US, E=support@company.com". The common fields and their meanings are shown below.

Field	Meaning
CN	Common Name. This is commonly a host name like www.server.com.
O	Organization
OU	Organizational Unit
L	Locality
S	State
C	Country
E	Email Address

If a field value contains a comma, it must be quoted.

SSLServerCert

Data Type

string

Default Value

""

Remarks

If using a TLS/SSL connection, this property can be used to specify the TLS/SSL certificate to be accepted from the server. Any other certificate that is not trusted by the machine is rejected.

This property can take the following forms:

Description	Example
A full PEM Certificate (example shortened for brevity)	-----BEGIN CERTIFICATE----- MIIChTCCAe4CAQAwDQYJKoZIhv......Qw== -----END CERTIFICATE-----
A path to a local file containing the certificate	C:\cert.cer
The public key (example shortened for brevity)	-----BEGIN RSA PUBLIC KEY----- MIGfMA0GCSq......AQAB -----END RSA PUBLIC KEY-----
The MD5 Thumbprint (hex values can also be either space or colon separated)	ecadbdda5a1529c58a1e9e09828d70e4
The SHA1 Thumbprint (hex values can also be either space or colon separated)	34a929226ae0819f2ec14b4a3d904f801cbb150d

If not specified, any certificate trusted by the machine is accepted.

Certificates are validated as trusted by the machine based on the System's trust store. The trust store used is the 'javax.net.ssl.trustStore' value specified for the system. If no value is specified for this property, Java's default trust store is used (for example, JAVA_HOME\lib\security\cacerts).

Use '*' to signify to accept all certificates. Note that this is not recommended due to security concerns.

SSHAuthMode

Data Type

string

Default Value

"Password"

Remarks

• None: No authentication will be performed. The current User value is ignored, and the connection will be logged in as anonymous.
• Password: The driver will use the values of User and Password to authenticate the user.
• Public_Key: The driver will use the values of User and SSHClientCert to authenticate the user. SSHClientCert must have a private key available for this authentication method to succeed.

SSHClientCert

Data Type

string

Default Value

""

Remarks

In order to use public key authentication, SSHClientCert must contain a certificate with a valid private key. The certificate's public key value is sent to the server along with a signature produced using the private key. The server will first check to see if the public key values match what is known for the user and then will attempt to use those values to verify the signature.

The SSHClientCertType field specifies the type of the certificate store specified by SSHClientCert. If the store is password protected, specify the password in SSHClientCertPassword.

SSHClientCert is used in conjunction with the SSHClientCertSubject field in order to specify client certificates. If SSHClientCert has a value, and SSHClientCertSubject is set, a search for a certificate is initiated. Please refer to the SSHClientCertSubject field for details.

Designations of certificate stores are platform-dependent.

The following are designations of the most common User and Machine certificate stores in Windows:

MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.
SPC	Software publisher certificates.

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (i.e. PKCS12 certificate store).

SSHClientCertPassword

Data Type

string

Default Value

""

Remarks

This property is only used when authenticating to SFTP servers with SSHAuthMode set to PublicKey and SSHClientCert set to a private key.

SSHClientCertSubject

Data Type

string

Default Value

"*"

Remarks

When loading a certificate the subject is used to locate the certificate in the store.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks the first certificate in the certificate store.

The certificate subject is a comma separated list of distinguished name fields and values. For instance "CN=www.server.com, OU=test, C=US, E=support@cdata.com". Common fields and their meanings are displayed below.

Field	Meaning
CN	Common Name. This is commonly a host name like www.server.com.
O	Organization
OU	Organizational Unit
L	Locality
S	State
C	Country
E	Email Address

If a field value contains a comma it must be quoted.

SSHClientCertType

Data Type

string

Default Value

"PUBLIC_KEY_FILE"

Remarks

The type of SSHClientCert certificate. This property can take one of the following values:

USER	For Windows, this specifies that the certificate store is a certificate store owned by the current user. Note: this store type is not available in Java.
MACHINE	For Windows, this specifies that the certificate store is a machine store. Note: this store type is not available in Java.
PFXFILE	The certificate store is the name of a PFX (PKCS12) file containing certificates.
PFXBLOB	The certificate store is a string (binary or base-64-encoded) representing a certificate store in PFX (PKCS12) format.
JKSFILE	The certificate store is the name of a Java Key Store (JKS) file containing certificates. Note: this store type is only available in Java.
JKSBLOB	The certificate store is a string (binary or base-64-encoded) representing a certificate store in Java Key Store (JKS) format. Note: this store type is only available in Java.
PEMKEY_FILE	The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
PEMKEY_BLOB	The certificate store is a string (binary or base-64-encoded) that contains a private key and an optional certificate.
PUBLIC_KEY_FILE	The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
PUBLIC_KEY_BLOB	The certificate store is a string (binary or base-64-encoded) that contains a PEM- or DER-encoded public key certificate.
SSHPUBLIC_KEY_BLOB	The certificate store is a string (binary or base-64-encoded) that contains an SSH-style public key.
P7BFILE	The certificate store is the name of a PKCS7 file containing certificates.
P7BBLOB	The certificate store is a string (binary) representing a certificate store in PKCS7 format.
SSHPUBLIC_KEY_FILE	The certificate store is the name of a file that contains an SSH-style public key.
PPKFILE	The certificate store is the name of a file that contains a PPK (PuTTY Private Key).
PPKBLOB	The certificate store is a string (binary) that contains a PPK (PuTTY Private Key).
XMLFILE	The certificate store is the name of a file that contains a certificate in XML format.
XMLBLOB	The certificate store is a string that contains a certificate in XML format.

SSHServer

Data Type

string

Default Value

""

Remarks

The SSH server.

SSHPort

Data Type

string

Default Value

"22"

Remarks

The SSH port.

SSHUser

Data Type

string

Default Value

""

Remarks

The SSH user.

SSHPassword

Data Type

string

Default Value

""

Remarks

The SSH password.

SSHServerFingerprint

Data Type

string

Default Value

""

Remarks

The SSH server fingerprint.

UseSSH

Data Type

bool

Default Value

false

Remarks

By default the driver will attempt to connect directly to MongoDB. When this option is enabled, the driver will instead establish an SSH connection with the SSHServer and tunnel the connection to MongoDB through it.

FirewallType

Data Type

string

Default Value

"NONE"

Remarks

This property specifies the protocol that the driver will use to tunnel traffic through the FirewallServer proxy.

Type	Default Port	Description
TUNNEL	80	When this is set, the driver opens a connection to MongoDB and traffic flows back and forth through the proxy.
SOCKS4	1080	When this is set, the driver sends data through the SOCKS 4 proxy specified by FirewallServer and FirewallPort and passes the FirewallUser value to the proxy, which determines if the connection request should be granted.
SOCKS5	1080	When this is set, the driver sends data through the SOCKS 5 proxy specified by FirewallServer and FirewallPort. If your proxy requires authentication, set FirewallUser and FirewallPassword to credentials the proxy recognizes.

FirewallServer

Data Type

string

Default Value

""

Remarks

This property specifies the IP address, DNS name, or host name of a proxy allowing traversal of a firewall. The protocol is specified by FirewallType: Use FirewallServer with this property to connect through SOCKS or do tunneling.

FirewallPort

Data Type

int

Default Value

0

Remarks

This specifies the TCP port for a proxy allowing traversal of a firewall. Use FirewallServer to specify the name or IP address. Specify the protocol with FirewallType.

FirewallUser

Data Type

string

Default Value

""

Remarks

The FirewallUser and FirewallPassword properties are used to authenticate against the proxy specified in FirewallServer and FirewallPort, following the authentication method specified in FirewallType.

FirewallPassword

Data Type

string

Default Value

""

Remarks

This property is passed to the proxy specified by FirewallServer and FirewallPort, following the authentication method specified by FirewallType.

Logfile

Data Type

string

Default Value

""

Remarks

Once this property is set, the driver will populate the log file as it carries out various tasks, such as when authentication is performed or queries are executed. If the specified file doesn't already exist, it will be created.

Connection strings and version information are also logged, though connection properties containing sensitive information are masked automatically.

If a relative filepath is supplied, the location of the log file will be resolved based on the path found in the Location connection property.

For more control over what is written to the log file, you can adjust the Verbosity property.

Log contents are categorized into several modules. You can show/hide individual modules using the LogModules property.

To edit the maximum size of a single logfile before a new one is created, see MaxLogFileSize.

If you would like to place a cap on the number of logfiles generated, use MaxLogFileCount.

Java Logging

Java logging is also supported. To enable Java logging, set Logfile to:

Logfile=JAVALOG://myloggername

As in the above sample, JAVALOG:// is a required prefix to use Java logging, and you will substitute your own Logger.

The supplied Logger's getLogger method is then called, using the supplied value to create the Logger instance. If a logging instance already exists, it will reference the existing instance.

When Java logging is enabled, the Verbosity will now correspond to specific logging levels.

Verbosity

Data Type

string

Default Value

"1"

Remarks

The verbosity level determines the amount of detail that the driver reports to the Logfile. Verbosity levels from 1 to 5 are supported. These are detailed in the Logging page.

LogModules

Data Type

string

Default Value

""

Remarks

Only the modules specified (separated by ';') will be included in the log file. By default all modules are included.

See the Logging page for an overview.

MaxLogFileSize

Data Type

string

Default Value

"100MB"

Remarks

When the limit is hit, a new log is created in the same folder with the date and time appended to the end. The default limit is 100 MB. Values lower than 100 kB will use 100 kB as the value instead.

Adjust the maximum number of logfiles generated with MaxLogFileCount.

MaxLogFileCount

Data Type

int

Default Value

-1

Remarks

When the limit is hit, a new log is created in the same folder with the date and time appended to the end and the oldest log file will be deleted.

The minimum supported value is 2. A value of 0 or a negative value indicates no limit on the count.

Adjust the maximum size of the logfiles generated with MaxLogFileSize.

Location

Data Type

string

Default Value

"%APPDATA%\\CData\\MongoDB Data Provider\\Schema"

Remarks

The path to a directory which contains the schema files for the driver (.rsd files for tables and views, .rsb files for stored procedures). The folder location can be a relative path from the location of the executable. The Location property is only needed if you want to customize definitions (for example, change a column name, ignore a column, and so on) or extend the data model with new tables, views, or stored procedures.

If left unspecified, the default location is "%APPDATA%\\CData\\MongoDB Data Provider\\Schema" with %APPDATA% being set to the user's configuration directory:

Platform	%APPDATA%
Windows	The value of the APPDATA environment variable
Mac	~/Library/Application Support
Linux	~/.config

BrowsableSchemas

Data Type

string

Default Value

""

Remarks

Listing the schemas from databases can be expensive. Providing a list of schemas in the connection string improves the performance.

Tables

Data Type

string

Default Value

""

Remarks

Listing the tables from some databases can be expensive. Providing a list of tables in the connection string improves the performance of the driver.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the tables you want in a comma-separated list. Each table should be a valid SQL identifier with any special characters escaped using square brackets, double-quotes or backticks. For example, Tables=TableA,[TableB/WithSlash],WithCatalog.WithSchema.`TableC With Space`.

Note that when connecting to a data source with multiple schemas or catalogs, you will need to provide the fully qualified name of the table in this property, as in the last example here, to avoid ambiguity between tables that exist in multiple catalogs or schemas.

Views

Data Type

string

Default Value

""

Remarks

Listing the views from some databases can be expensive. Providing a list of views in the connection string improves the performance of the driver.

This property can also be used as an alternative to automatically listing views if you already know which ones you want to work with and there would otherwise be too many to work with.

Specify the views you want in a comma-separated list. Each view should be a valid SQL identifier with any special characters escaped using square brackets, double-quotes or backticks. For example, Views=ViewA,[ViewB/WithSlash],WithCatalog.WithSchema.`ViewC With Space`.

Note that when connecting to a data source with multiple schemas or catalogs, you will need to provide the fully qualified name of the table in this property, as in the last example here, to avoid ambiguity between tables that exist in multiple catalogs or schemas.

AutoCache

Data Type

bool

Default Value

false

Remarks

When AutoCache = true, the driver automatically maintains a cache of your table's data in the database of your choice.

Setting the Caching Database

When AutoCache = true, the driver caches to a simple, file-based cache. You can configure its location or cache to a different database with the following properties:

• CacheLocation: Specifies the path to the file store.
• CacheDriver and CacheConnection: Specifies a driver to a database and the connection string.

See Also

• CacheMetadata: This property reduces the amount of metadata that crosses the network by persisting table schemas retrieved from the MongoDB metadata. Metadata then needs to be retrieved only once instead of every connection.
• Explicitly Caching Data: This section provides more examples of using AutoCache in Offline mode.
• CACHE Statements: You can use the CACHE statement to persist any SELECT query, as well as manage the cache; for example, refreshing schemas.

CacheDriver

Data Type

string

Default Value

""

Remarks

You can cache to any database for which you have a JDBC driver, including CData JDBC drivers.

The cache database is determined based on the CacheDriver and CacheConnection properties. The CacheDriver is the name of the JDBC driver class that you want to use to cache data.

Note that you must also add the CacheDriver JAR file to the classpath.

The following examples show how to cache to several major databases. Refer to CacheConnection for more information on the JDBC URL syntax and typical connection properties.

Derby and Java DB

The driver simplifies Derby configuration. Java DB is the Oracle distribution of Derby. The JAR file is shipped in the JDK. You can find the JAR file, derby.jar, in the db subfolder of the JDK installation. In most caching scenarios, you need to specify only the following, after adding derby.jar to the classpath:

jdbc:mongodb:CacheLocation='c:/Temp/cachedir';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

To customize the Derby JDBC URL, use CacheDriver and CacheConnection. For example, to cache to an in-memory database, use a JDBC URL like the following:

jdbc:mongodb:CacheDriver=org.apache.derby.jdbc.EmbeddedDriver;CacheConnection='jdbc:derby:memory';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

SQLite

The following is a JDBC URL for the SQLite JDBC driver:

jdbc:mongodb:CacheDriver=org.sqlite.JDBC;CacheConnection='jdbc:sqlite:C:/Temp/sqlite.db';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

MySQL

The following is a JDBC URL for the included CData JDBC Driver for MySQL:

  jdbc:mongodb:Cache Driver=cdata.jdbc.mysql.MySQLDriver;Cache Connection='jdbc:mysql:Server=localhost;Port=3306;Database=cache;User=root;Password=123456';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

  

SQL Server

The following JDBC URL uses the Microsoft JDBC Driver for SQL Server:

jdbc:mongodb:Cache Driver=com.microsoft.sqlserver.jdbc.SQLServerDriver;Cache Connection='jdbc:sqlserver://localhost\sqlexpress:7437;user=sa;password=123456;databaseName=Cache';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

Oracle

The following is a JDBC URL for the Oracle Thin Client:

jdbc:mongodb:Cache Driver=oracle.jdbc.OracleDriver;CacheConnection='jdbc:oracle:thin:scott/tiger@localhost:1521:orcldb';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

NOTE: If using a version of Oracle older than 9i, the cache driver will instead be oracle.jdbc.driver.OracleDriver .

PostgreSQL

The following JDBC URL uses the official PostgreSQL JDBC driver:

jdbc:mongodb:CacheDriver=cdata.jdbc.postgresql.PostgreSQLDriver;CacheConnection='jdbc:postgresql:User=postgres;Password=admin;Database=postgres;Server=localhost;Port=5432;';Server=127.0.0.1;Port=27017;Database=test;User=test;Password=test;

CacheConnection

Data Type

string

Default Value

""

Remarks

The cache database is determined based on the CacheDriver and CacheConnection properties. Both properties are required to use the cache database. Examples of common cache database settings can be found below. For more information on setting the caching database's driver, refer to CacheDriver.

The connection string specified in the CacheConnection property is passed directly to the underlying CacheDriver. Consult the documentation for the specific JDBC driver for more information on the available properties. Make sure to include the JDBC driver in your application's classpath.

Derby and Java DB

The driver simplifies caching to Derby, only requiring you to set the CacheLocation property to make a basic connection.

Alternatively, you can configure the connection to Derby manually using CacheDriver and CacheConnection. The following is the Derby JDBC URL syntax:

jdbc:derby:[subsubprotocol:][databaseName][;attribute=value[;attribute=value] ... ]

For example, to cache to an in-memory database, use the following:

jdbc:derby:memory

SQLite

To cache to SQLite, you can use the SQLite JDBC driver. The following is the syntax of the JDBC URL:

jdbc:sqlite:dataSource

• Data Source: The path to an SQLite database file. Or, use a value of :memory to cache in memory.

MySQL

The installation includes the CData JDBC Driver for MySQL. The following is an example JDBC URL:

jdbc:mysql:User=root;Password=root;Server=localhost;Port=3306;Database=cache

The following are typical connection properties:

• Server: The IP address or domain name of the server you want to connect to.
• Port: The port that the server is running on.
• User: The user name provided for authentication to the database.
• Password: The password provided for authentication to the database.
• Database: The name of the database.

SQL Server

The JDBC URL for the Microsoft JDBC Driver for SQL Server has the following syntax:

jdbc:sqlserver://[serverName[\instance][:port]][;database=databaseName][;property=value[;property=value] ... ]

For example:

jdbc:sqlserver://localhost\sqlexpress:1433;integratedSecurity=true

The following are typical SQL Server connection properties:

• Server: The name or network address of the computer running SQL Server. To connect to a named instance instead of the default instance, this property can be used to specify the host name and the instance, separated by a backslash.
• Port: The port SQL Server is running on.
• Database: The name of the SQL Server database.
• Integrated Security: Set this option to true to use the current Windows account for authentication. Set this option to false if you are setting the User and Password in the connection.

  To use integrated security, you will also need to add sqljdbc_auth.dll to a folder on the Windows system path. This file is located in the auth subfolder of the Microsoft JDBC Driver for SQL Server installation. The bitness of the assembly must match the bitness of your JVM.

• User Id: The user name provided for authentication with SQL Server. This property is only needed if you are not using integrated security.
• Password: The password provided for authentication with SQL Server. This property is only needed if you are not using integrated security.

Oracle

The following is the conventional JDBC URL syntax for the Oracle JDBC Thin driver:

jdbc:oracle:thin:[userId/password]@[//]host[[:port][:sid]]

For example:

jdbc:oracle:thin:scott/tiger@myhost:1521:orcl

The following are typical connection properties:

• Data Source: The connect descriptor that identifies the Oracle database. This can be a TNS connect descriptor, an Oracle Net Services name that resolves to a connect descriptor, or, after version 11g, an Easy Connect naming (the host name of the Oracle server with an optional port and service name).

• Password: The password provided for authentication with the Oracle database.
• User Id: The user Id provided for authentication with the Oracle database.

PostgreSQL

The following is the JDBC URL syntax for the official PostgreSQL JDBC driver:

jdbc:postgresql:[//[host[:port]]/]database[[?option=value][[&option=value][&option=value] ... ]]

For example, the following connection string connects to a database on the default host (localhost) and port (5432):

jdbc:postgresql:postgres

The following are typical connection properties:

• Host: The address of the server hosting the PostgreSQL database.
• Port: The port used to connect to the server hosting the PostgreSQL database.
• Database: The name of the database.
• User name: The user Id provided for authentication with the PostgreSQL database. You can specify this in the JDBC URL with the "user" parameter.
• Password: The password provided for authentication with the PostgreSQL database.

CacheLocation

Data Type

string

Default Value

"%APPDATA%\\CData\\MongoDB Data Provider"

Remarks

The CacheLocation is a simple, file-based cache. The driver uses Java DB, Oracle's distribution of the Derby database. To cache to Java DB, you will need to add the Java DB JAR file to the classpath. The JAR file, derby.jar, is shipped in the JDK and located in the db subfolder of the JDK installation.

If left unspecified, the default location is "%APPDATA%\\CData\\MongoDB Data Provider" with %APPDATA% being set to the user's configuration directory:

Platform	%APPDATA%
Windows	The value of the APPDATA environment variable
Mac	~/Library/Application Support
Linux	~/.config

See Also

• AutoCache: Set to implicitly create and maintain a cache for later offline use.
• CacheMetadata: Set to persist the MongoDB catalog in CacheLocation.

CacheTolerance

Data Type

int

Default Value

600

Remarks

The tolerance for stale data in the cache specified in seconds. This only applies when AutoCache is used. The driver checks with the data source for newer records after the tolerance interval has expired. Otherwise, it returns the data directly from the cache.

Offline

Data Type

bool

Default Value

false

Remarks

When Offline = true, all queries execute against the cache as opposed to the live data source. In this mode, certain queries like INSERT, UPDATE, DELETE, and CACHE are not allowed.

CacheMetadata

Data Type

bool

Default Value

false

Remarks

As you execute queries with this property set, table metadata in the MongoDB catalog are cached to the file store specified by CacheLocation if set or the user's home directory otherwise. A table's metadata will be retrieved only once, when the table is queried for the first time.

When to Use CacheMetadata

The driver automatically persists metadata in memory for up to two hours when you first discover the metadata for a table or view and therefore, CacheMetadata is generally not required. CacheMetadata becomes useful when metadata operations are expensive such as when you are working with large amounts of metadata or when you have many short-lived connections.

When Not to Use CacheMetadata

• When you are working with volatile metadata: Metadata for a table is only retrieved the first time the connection to the table is made. To pick up new, changed, or deleted columns, you would need to delete and rebuild the metadata cache. Therefore, it is best to rely on the in-memory caching for cases where metadata changes often.
• When you are caching to a database: CacheMetadata can only be used with CacheLocation. If you are caching to another database with the CacheDriver and CacheConnection properties, use AutoCache to cache implicitly. Or, use CACHE Statements to cache explicitly.

BatchSize

Data Type

int

Default Value

0

Remarks

When BatchSize is set to a value greater than 0, the batch operation will split the entire batch into separate batches of size BatchSize. The split batches will then be submitted to the server individually. This is useful when the server has limitations on the size of the request that can be submitted.

Setting BatchSize to 0 will submit the entire batch as specified.

ConnectionLifeTime

Data Type

int

Default Value

0

Remarks

The maximum lifetime of a connection in seconds. Once the time has elapsed, the connection object is disposed. The default is 0 which indicates there is no limit to the connection lifetime.

ConnectOnOpen

Data Type

bool

Default Value

false

Remarks

When set to true, a connection will be made to MongoDB when the connection is opened. This property enables the Test Connection feature available in various database tools.

This feature acts as a NOOP command as it is used to verify a connection can be made to MongoDB and nothing from this initial connection is maintained.

Setting this property to false may provide performance improvements (depending upon the number of times a connection is opened).

DataModel

Data Type

string

Default Value

"DOCUMENT"

Remarks

When setting DataModel to Relational, the discovery of child tables extends to root level elements and those found within top-level array elements.

FlattenArrays

Data Type

string

Default Value

""

Remarks

By default, nested arrays are returned as strings of JSON. The FlattenArrays property can be used to flatten the elements of nested arrays into columns of their own. This is only recommended for arrays that are expected to be short.

Set FlattenArrays to the number of elements you want to return from nested arrays. The specified elements are returned as columns. The zero-based index is concatenated to the column name. Other elements are ignored.

For example, you can return an arbitrary number of elements from an array of strings:

["FLOW-MATIC","LISP","COBOL"]

When FlattenArrays is set to 1, the preceding array is flattened into the following table:

Column Name	Column Value
languages.0	FLOW-MATIC

Setting FlattenArrays to -1 will flatten all the elements of nested arrays.

FlattenObjects

Data Type

bool

Default Value

true

Remarks

Set FlattenObjects to true to flatten object properties into columns of their own. Otherwise, objects nested in arrays are returned as strings of JSON. To generate the column name, the driver concatenates the property name onto the object name with a dot.

For example, you can flatten the nested objects below at connection time:

[

     { "grade": "A", "score": 2 },

     { "grade": "A", "score": 6 },

     { "grade": "A", "score": 10 },

     { "grade": "A", "score": 9 },

     { "grade": "B", "score": 14 }

]

When FlattenObjects is set to true and FlattenArrays is set to 1, the preceding array is flattened into the following table:

Column Name	Column Value
grades.0.grade	A
grades.0.score	2

GenerateSchemaFiles

Data Type

string

Default Value

"Never"

Remarks

GenerateSchemaFiles enables you to save the table definitions identified by Automatic Schema Discovery. This property outputs schemas to .rsd files in the path specified by Location.

Available settings are the following:

• Never: A schema file will never be generated.
• OnUse: A schema file will be generated the first time a table is referenced, provided the schema file for the table does not already exist.
• OnStart: A schema file will be generated at connection time for any tables that do not currently have a schema file.
• OnCreate: A schema file will be generated by when running a CREATE TABLE SQL query.

Note that if you want to regenerate a file, you will first need to delete it.

Generate Schemas with SQL

When you set GenerateSchemaFiles to OnUse, the driver generates schemas as you execute SELECT queries. Schemas are generated for each table referenced in the query.

When you set GenerateSchemaFiles to OnCreate, schemas are only generated when a CREATE TABLE query is executed.

Generate Schemas on Connection

Another way to use this property is to obtain schemas for every table in your database when you connect. To do so, set GenerateSchemaFiles to OnStart and connect.

Alternatives to Static Schemas

If your data structures are volatile, consider setting GenerateSchemaFiles to Never and using dynamic schemas. See Automatic Schema Discovery for more information about dynamic schemas.

Editing Schemas

Schema files have a simple format that makes them easy to modify. See Custom Schema Definitions for more information.

MaxRows

Data Type

int

Default Value

-1

Remarks

Limits the number of rows returned rows when no aggregation or group by is used in the query. This helps avoid performance issues at design time.

NoCursorTimeout

Data Type

bool

Default Value

false

Remarks

The server normally times out idle cursors after an inactivity period (10 minutes) to prevent excess memory use. Set this option to prevent that.

Other

Data Type

string

Default Value

""

Remarks

The properties listed below are available for specific use cases. Normal driver use cases and functionality should not require these properties.

Specify multiple properties in a semicolon-separated list.

Caching Configuration

CachePartial=True	Caches only a subset of columns, which you can specify in your query.
QueryPassthrough=True	Passes the specified query to the cache database instead of using the SQL parser of the driver.

Integration and Formatting

DefaultColumnSize	Sets the default length of string fields when the data source does not provide column length in the metadata. The default value is 2000.
ConvertDateTimeToGMT	Determines whether to convert date-time values to GMT, instead of the local time of the machine.
RecordToFile=filename	Records the underlying socket data transfer to the specified file.

Pagesize

Data Type

int

Default Value

4096

Remarks

The Pagesize property affects the maximum number of results to return per page from MongoDB. Setting a higher value may result in better performance at the cost of additional memory allocated per page consumed.

PoolIdleTimeout

Data Type

int

Default Value

60

Remarks

The allowed idle time a connection can remain in the pool until the connection is closed. The default is 60 seconds.

PoolMaxSize

Data Type

int

Default Value

100

Remarks

The maximum connections in the pool. The default is 100. To disable this property, set the property value to 0 or less.

PoolMinSize

Data Type

int

Default Value

1

Remarks

The minimum number of connections in the pool. The default is 1.

PoolWaitTime

Data Type

int

Default Value

60

Remarks

The max seconds to wait for a connection to become available. If a new connection request is waiting for an available connection and exceeds this time, an error is thrown. By default, new requests wait forever for an available connection.

PseudoColumns

Data Type

string

Default Value

""

Remarks

This setting is particularly helpful in Entity Framework, which does not allow you to set a value for a pseudo column unless it is a table column. The value of this connection setting is of the format "Table1=Column1, Table1=Column2, Table2=Column3". You can use the "*" character to include all tables and all columns; for example, "*=*".

QueryPassthrough

Data Type

bool

Default Value

false

Remarks

When set to 'True', the specified query will be passed to MongoDB as-is. Currently only these shell commands are supported:

• db.myCollection.find() returns all fields for all records in the collection.
• db.myCollection.find({ query }) returns all fields for all records in the collection matching the query.
• db.myCollection.find({ query }, { projection }) returns the fields in the projection, for all records matching the query.
• All of the above forms accept a .json() suffix. This returns a single column containing the matching documents as JSON instead of individual fields.

Note that you can use the EVAL stored procedure to execute other JavaScript functions.

Readonly

Data Type

bool

Default Value

false

Remarks

If this property is set to true, the driver will allow only SELECT queries. INSERT, UPDATE, DELETE, and stored procedure queries will cause an error to be thrown.

ReadPreference

Data Type

string

Default Value

"primary"

Remarks

This property enables you to execute queries to a member in a replica set other other than the primary member. Accepted values are the following:

• primary: All SELECT queries are executed against the primary server.
• primaryPreferred: If the primary server is not available, SELECT queries are executed to a secondary server.
• secondary: All SELECT queries are executed to the secondary servers.
• secondaryPreferred: SELECT queries are executed to a secondary server if one is available. Otherwise, the queries are executed to the primary server.
• nearest: SELECT queries are executed to the server with the least latency.

When to Use ReadPreference

When this property is set, query results may not reflect the latest changes if a write operation has not yet been replicated to a secondary machine. You can use ReadPreference to accomplish the following, with some risk that the driver will return stale data:

• Configure failover queries: If the primary server is unavailable, you can set this property to "primaryPreferred" to continue to execute queries online.
• Execute faster queries to geographically distributed replica sets: If your deployment uses multiple data centers, setting ReadPreference to "nearest" can result in faster queries, as the driver executes SELECT queries to whichever replica set member has the lowest latency.

When directing the driver to execute SELECT statements to a secondary server, SlaveOK must also be set. Otherwise, the driver will return an error response.

RowScanDepth

Data Type

int

Default Value

100

Remarks

The columns in a table must be determined by scanning table rows. This value determines the maximum number of rows that will be scanned.

Setting a high value may decrease performance. Setting a low value may prevent the data type from being determined properly, especially when there is null data.

Setting to a value of -1 causes the driver to scan an arbitrary number of rows until it reaches the final row.

RTK

Data Type

string

Default Value

""

Remarks

The RTK property may be used to license a build. See the included licensing file to see how to set this property. The runtime key is only available if you purchased an OEM license.

SlaveOK

Data Type

bool

Default Value

false

Remarks

This property sets whether the driver is allowed to read from secondary (slave) servers in a replica set. You can fine-tune how the driver queries secondary servers with ReadPreference.

SupportEnhancedSQL

Data Type

bool

Default Value

true

Remarks

When SupportEnhancedSQL = true, the driver offloads as much of the SELECT statement processing as possible to MongoDB and then processes the rest of the query in memory. In this way, the driver can execute unsupported predicates, joins, and aggregation.

When SupportEnhancedSQL = false, the driver limits SQL execution to what is supported by the MongoDB API.

Execution of Predicates

The driver determines which of the clauses are supported by the data source and then pushes them to the source to get the smallest superset of rows that would satisfy the query. It then filters the rest of the rows locally. The filter operation is streamed, which enables the driver to filter effectively for even very large datasets.

Execution of Joins

The driver uses various techniques to join in memory. The driver trades off memory utilization against the requirement of reading the same table more than once.

Execution of Aggregates

The driver retrieves all rows necessary to process the aggregation in memory.

Timeout

Data Type

int

Default Value

60

Remarks

If Timeout = 0, operations do not time out. The operations run until they complete successfully or until they encounter an error condition.

If Timeout expires and the operation is not yet complete, the driver throws an exception.

TypeDetectionScheme

Data Type

string

Default Value

"RowScan"

Remarks

None	Setting TypeDetectionScheme to None will return all columns as a string type. Cannot be combined with other options.
RowScan	Setting TypeDetectionScheme to RowScan will scan rows to heuristically determine the data type. The RowScanDepth determines the number of rows to be scanned. Can be used with Recent.
Recent	Setting TypeDetectionScheme to 'RowScan,Recent' will instead execute the rowscan on the most recent documents inserted into the collection. This is a more expensive operation that may be significantly slower on large datasets.

UseConnectionPooling

Data Type

bool

Default Value

false

Remarks

This property enables connection pooling. The default is false. See Connection Pooling for information on using connection pools.

UseFindAPI

Data Type

string

Default Value

"False"

Remarks

Amazon DocumentDB doesn't support the legacy OP_QUERY interface, so this must be set to True to query DocumentDB clusters with db.collection.find() instead.

WriteConcern

Data Type

string

Default Value

"0"

Remarks

Requests acknowledgment that the write operation has propagated to the specified number of mongod instances.

WriteConcernJournaled

Data Type

bool

Default Value

true

Remarks

It requests acknowledgment that the mongod instances, as specified in the WriteConcern property, have written to the on-disk journal.

WriteConcernTimeout

Data Type

string

Default Value

"0"

Remarks

This option specifies a time limit, in milliseconds, for the write concern.

WriteScheme

Data Type

string

Default Value

"Metadata"

Remarks

Sets whether the object type for inserted or updated objects is determined from the existing column metadata or the input value type. When the default value Metadata is used, the driver uses the data type as determined by the TypeDetectionScheme for objects pushed to MongoDB. When the value is set to RawValue, the type of the object in the INSERT determines what type is used for MongoDB.

For example, if you have a field 'c1' in MongoDB defined as String type, the metadata returns the column as String as well. In the following query, the resulting field in MongoDB is therefore defined as String when using WriteScheme=Metadata. But when using RawValue, the inserting field type is Date instead since the FROM_UNIXTIME() function returns an actual Date object:

INSERT into Table1 (c1) VALUES(FROM_UNIXTIME(1636910867039, 0))

Inserting an empty array

With WriteScheme=RawValue, use the following syntax to insert an empty BSON array:

INSERTINTO t1 ("c1")VALUES(())

This returns an empty array:

"c1":[]