ODBC Advanced Optional Fields
ODBC advanced options allow debugging and fine-tuning of the ODBC driver used by the Internet Database Connector.
Note
IDC has been deprecated because it does not provide enough security for data connections. IIS 6.0 will be the last version to include IDC.
For more details about these options, consult your ODBC driver documentation or the ODBC Software Development Kit (SDK). The format in the IDC file is:
ODBCOptions: Option Name=Value[,Option Name=Value...]
For example, to stop the SQL statement from running for more than 10 seconds and enabling tracing of ODBC function calls, in the IDC file you would specify:
ODBCOptions: SQL_QUERY_TIMEOUT=10, SQL_OPT_TRACE=1, SQL_OPT_TRACEFILE=C:\Sql.log
Option Name |
Value |
Meaning |
|---|---|---|
SQL_ACCESS_MODE |
0 = Read/Write 1 = Read Only |
An indicator for the ODBC driver or data source that the connection is not required to support SQL statements that cause updates to occur. This mode can be used to optimize locking strategies, transaction management, or other areas as appropriate to the driver or data source. The driver is not required to prevent such statements from being submitted to the data source. The behavior of the driver and data source when asked to process SQL statements that are not read-only during a read-only connection is implementation-defined. SQL_ACCESS_MODE set to 0 is the default, which allows reading and writing. |
SQL_LOGIN_TIMEOUT |
Integer |
The number of seconds to wait for a logon request to complete before disconnecting. The default is driver-dependent and must be nonzero. If the value is 0, the timeout is disabled and a connection attempt will wait indefinitely. If the specified timeout exceeds the maximum log on timeout in the data source, the driver substitutes that value. |
SQL_OPT_TRACE |
0 = Trace off 1 = Trace on |
When tracing is on, each ODBC function call made by Httpodbc.dll is written to the trace file. You can specify a trace file with the SQL_OPT_TRACEFILE option. If the file already exists, the ODBC appends to the file. Otherwise, it creates the file. If tracing is on and no trace file has been specified, ODBC writes to the file Sql.log. |
SQL_OPT_TRACEFILE |
File name |
The name of the trace file to use when SQL_OPT_TRACE=1. The default is SQL.LOG |
SQL_PACKET_SIZE |
Integer |
The network packet size, in bytes, to be used to exchange information between the database management system (DBMS) and the Web Server. Note Many data sources either do not support this option or can return only the network packet size. If the specified size exceeds the maximum packet size or is smaller than the minimum packet size, the driver substitutes that value. |
SQL_TRANSLATE_DLL |
File name |
The name of a DLL containing the functions SQLDriverToDataSource and SQLDataSourceToDriver that the driver loads and uses to perform tasks such as character-set translation. |
SQL_TRANSLATE_OPTION |
Integer |
Value controlling translation functionality, which is specific to the translation DLL being used. Consult the documentation for the driver and translation DLL for details. |
SQL_TXN_ISOLATION |
Integer 1=Read Uncommitted 2=Read Committed 4=Repeatable Read 8=Serializable 16=Versioning |
Sets the transaction isolation level. The Internet Database Connector does not support transactions than span more than the request in the .idc file. However, for some DBMSs, setting the SQL_TXN_ISOLATION option to 1 (Read Uncommitted) will result in higher concurrency and therefore better performance. However, with this setting, data that has not been committed to the database by other transactions may be retrieved. |
SQL_MAX_LENGTH |
Integer |
The maximum amount of data that the driver returns from a character or binary column. This option is intended to reduce network traffic and should only be used when the data source (as opposed to the driver) in a multiple-tier driver can implement it. |
SQL_MAX_ROWS |
Integer |
The maximum number of rows to return for a SELECT statement. If the value equals 0 (the default), then the driver returns all rows. This option is intended to reduce network traffic when the data source itself can limit the return rows, as opposed to the MaxRecords built-in variable in the Internet Database Connector, which limits the rows fetched. |
SQL_NOSCAN |
0=Scan for and convert escape clauses 1=Do not scan for and convert escape clauses |
Specifies whether the driver does not scan SQL strings for escape clauses. If set to 0 (the default), the driver scans SQL strings for escape clauses. If set to 1, the driver does not scan SQL strings for escape clauses; instead, the driver sends the statement directly to the data source. If your SQL statement does not contain any ODBC escape clauses, a special syntax enclosed by curly braces ( { } ), then setting this option to 1 will provide a small performance gain by directing the driver to not scan the SQL string. |
SQL_QUERY_TIMEOUT |
Integer 0=No timeout |
The number of seconds to wait for a SQL statement to execute before canceling the query. When set to 0 (the default) there is no timeout. If the specified timeout exceeds the maximum timeout in the data source, or is smaller than the minimum timeout, the driver substitutes that value. |
Integer |
Driver Specific |
Driver-specific option values can be specified in the form number=value. For example, |
Requirements
Client: Requires Windows XP Professional, Windows 2000 Professional, or Windows NT Workstation 4.0.
Server: Requires Windows Server 2003, Windows 2000 Server, or Windows NT Server 4.0.
Product: IIS