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SQLSetConnectAttrForDbcInfo Function

  • Стаття

Conformance
Version Introduced: ODBC 3.81 Standards Compliance: ODBC

Summary
SQLSetConnectAttrForDbcInfo is the same as SQLSetConnectAttr, but it sets the attribute on the connection information token instead of on the connection handle.

Syntax

  
SQLRETURN  SQLSetConnectAttrForDbcInfo(  
                SQLHDBC_INFO_TOKEN    hDbcInfoToken,  
                SQLINTEGER            Attribute,  
                SQLPOINTER            ValuePtr,  
                SQLINTEGER            StringLength );

Arguments

hDbcInfoToken
[Input] Token handle.

Attribute
[Input] Attribute to set. The list of valid attributes is driver specific and the same as for SQLSetConnectAttr.

ValuePtr
[Input] Pointer to the value to be associated with Attribute. Depending on the value of Attribute, ValuePtr will be a 32-bit unsigned integer value or will point to a null-terminated character string. Note that if the Attribute argument is a driver-specific value, the value in ValuePtr may be a signed integer.

StringLength
[Input] If Attribute is an ODBC-defined attribute and ValuePtr points to a character string or a binary buffer, this argument should be the length of *ValuePtr. For character string data, this argument should contain the number of bytes in the string.

If Attribute is an ODBC-defined attribute and ValuePtr is an integer, StringLength is ignored.

If Attribute is a driver-defined attribute, the application indicates the nature of the attribute to the Driver Manager by setting the StringLength argument. StringLength can have the following values:

  • If ValuePtr is a pointer to a character string, then StringLength is the length of the string or SQL_NTS.

  • If ValuePtr is a pointer to a binary buffer, then the application places the result of the SQL_LEN_BINARY_ATTR(length) macro in StringLength. This places a negative value in StringLength.

  • If ValuePtr is a pointer to a value other than a character string or a binary string, then StringLength should have the value SQL_IS_POINTER.

  • If ValuePtr contains a fixed-length value, then StringLength is either SQL_IS_INTEGER or SQL_IS_UINTEGER, as appropriate.

Returns

SQL_SUCCESS, SQL_SUCCESS_WITH_INFO, SQL_ERROR, or SQL_INVALID_HANDLE.

Diagnostics

Same as SQLSetConnectAttr, except that the Driver Manager will use a HandleType of SQL_HANDLE_DBC_INFO_TOKEN and a Handle of hDbcInfoToken.

Remarks

SQLSetConnectAttrForDbcInfo is the same as SQLSetConnectAttr, but it sets the attribute on the connection information token, instead of on the connection handle. For example, if SQLSetConnectAttr does not recognize an attribute, SQLSetConnectAttrForDbcInfo should also return SQL_ERROR for that attribute.

Whenever driver returns SQL_ERROR or SQL_INVALID_HANDLE, the driver should ignore this attribute to compute the pool ID. Also, the Driver Manager will obtain the diagnostic information from hDbcInfoToken, and return SQL_SUCCESS_WITH_INFO to the application in SQLConnect and SQLDriverConnect. Therefore, an application can retrieve details about why some attributes cannot be set.

Applications should not call this function directly. An ODBC driver that supports driver-aware connection pooling must implement this function.

Include sqlspi.h for ODBC driver development.

See Also

Developing an ODBC Driver
Driver-Aware Connection Pooling
Developing Connection-Pool Awareness in an ODBC Driver