The following tables define all possible ODBC connection attributes for the FreeTDS ODBC driver. Which ones you'll need depends on how you set yourself up. They may appear in your connection string, or in odbc.ini.
Table 4.1. Connection attributes used only in connection strings
| Name | Possible Values | Default | Meaning |
|---|---|---|---|
DSN | A valid DSN entry | none | The DSN to which FreeTDS should connect. FreeTDS will search odbc.ini for entry. It lets you specify a connection as for SQLConnect, but using SQLDriverConnect. Do not use Servername and DSN together. |
UID | Any valid username | none | The username to be used when connecting. To use domain authentication, specify the domain using the format domain\username. |
PWD | Any | empty | The password to be used when connecting. |
WSID | Any | Computer name | The name of the local computer, sent to server. Can be specified only for a DSN-less connection. |
DateTimeFmt | strftime(3) format, %z for fractions of seconds | %Y-%m-%d %H:%M:%S.%z | Format used to convert datetime, datetime2 and similar types to character.
Can also be set with the SQL_COPT_TDSODBC_DATETIME_FORMAT connection attribute (see odbcss.h).
A precision can be specified for fractions of seconds, for instance %3z for milliseconds. |
DateFmt | as above | %Y-%m-%d | Format used to convert date to character.
Can also be set with the SQL_COPT_TDSODBC_DATE_FORMAT connection attribute. |
TimeFmt | as above | %H:%M:%S.%z | Format used to convert time to character.
Can also be set with the SQL_COPT_TDSODBC_TIME_FORMAT connection attribute. |
Table 4.2. Connection attributes that may appear in odbc.ini
| Name | Possible Values | Default | Meaning |
|---|---|---|---|
Servername | A valid freetds.conf server section | none | A freetds.conf servername, not a hostname as known to DNS. If you want to use ODBC-only configuration, use Server instead. |
Server | A server name or (ip) address | none | Hostname of a server. Used in an ODBC-only configuration. To specify a Microsoft SQL Server instance, use the form server\instance. |
Port | Any TCP port | Depends on the TDS version specified with configure | The TCP port where the servername is listening. |
TDS_Version | Any valid protocol version | Depends on the TDS version specified with configure | TDS protocol version to use (e.g., 5.0, 7.4). |
ClientCharset or Client_Charset | A name recognized by the iconv library linked to FreeTDS. Corresponds to client charset in freetds.conf.
Client_Charset is for compatibility with NCBI C++ ToolKit. | ISO 8859-1 | Character set (encoding) used by the client. |
APP | Free form text, up to 30 characters. | none | Application name. Identifies the connecting application to the server. |
Language | Any | us_english | (Human) language the server should use for error messages. |
Address | Any | none | IP address of the servername. Useful if you want to specify a server by address, rather than by name. The format is ip,port or simply ip in standard dotted-decimal notation. |
Database | Any | none | Specify which database you want to access. If the database does not exist or the user lacks permission to access it, the connection will fail. |
TextSize | Any | Server-dependent | Maximum size returned from server for blobs. |
PacketSize | Any | Server-dependent | Size of packets to server. Some users saw some performance gain by increasing this value. Normally you shouldn't set it. |
Trusted_Connection | Yes/No | No | Use your current account instead of UID/PWD attributes. This option require SSPI or Kerberos and supersedes any UID/PWD attributes passed from the application. |
Encryption | off/request/require/strict | off | Specify encryption. See encryption on freetds.conf |
Encrypt | yes/no/true/false/optional/mandatory/strict | optional | Specify encryption.
Similar to encryption on freetds.conf but Microsoft compatible. |
ServerCertificate | Any | none | File that holds root certificates (in PEM format) to verify server certificate, used during an encrypted connection.
If not specify or empty any certificate will be accepted from server.
If you specify system FreeTDS will use system wide certificate list.
If a certificate is not installed server can generate a self signed certificate, in this case is useful to disable certificate validation (which is the default).
Note that is not possible to specify a directory as usually database servers does not use a certificate signed by a public global certification authority.
Microsoft compatible. |
HostNameInCertificate | Server name | null | Server name to match certificate name. Microsoft compatible. |
MARS_Connection | Yes/No | No | Enable MARS for this connection. |
UseNTLMv2 | Yes/No | Yes | Use NTLMv2 instead of normal NTLM. Disable this option if your Windows domain have this setting. |
REALM | Machine domain | none | Kerberos REALM. |
ServerSPN | Any valid SPN | MSSQLSvc/server FQDN:port or MSSQLSvc/server FQDN:instance | Full server Kerberos SPN. See SPN on freetds.conf. |
AttachDbFilename | server filename (mdf/sdf) | none | MSSQL allow to attach a database while connecting to a server.
This setting allow to do it. You should specify Database attribute to set the name of the database that will be used. |
DumpFile | Any | File name where to dump logs. | |
DumpFileAppend | Yes/No | No | Append to dump file instead of overwriting it. |
DebugFlags | Any | Debug flags. See freetds.conf entries. | |
ApplicationIntent | ReadWrite/ReadOnly | ReadWrite | Tell application intent. See read-only intent on freetds.conf. |
Timeout | Integer number | Query timeout in seconds. | |
ConnectionTimeout | Integer number | Connection timeout in seconds. |