SQLAllocHandle

Function

SQLAllocHandle is used to allocate environment, connection, statement, or descriptor handles. This function replaces the deprecated ODBC 2.x functions SQLAllocEnv, SQLAllocConnect, and SQLAllocStmt.

Prototype

    
         SQLRETURN SQLAllocHandle(SQLSMALLINT   HandleType,    
                         SQLHANDLE     InputHandle,     
                         SQLHANDLE     *OutputHandlePtr);

Parameter

**Table 1** SQLAllocHandle parameters
Keyword	Parameter Description
HandleType	Type of handle to be allocated by SQLAllocHandle. The value must be one of the following: SQL_HANDLE_ENV (environment handle) SQL_HANDLE_DBC (connection handle) SQL_HANDLE_STMT (statement handle) SQL_HANDLE_DESC (descriptor handle) The handle application sequence is: SQL_HANDLE_ENV > SQL_HANDLE_DBC > SQL_HANDLE_STMT. The handle applied later depends on the handle applied prior to it.
InputHandle	Existing handle to use as a context for the new handle being allocated. If HandleType is set to SQL_HANDLE_ENV, this parameter is set to SQL_NULL_HANDLE. If HandleType is set to SQL_HANDLE_DBC, this parameter value must be an environment handle. If HandleType is set to SQL_HANDLE_STMT or SQL_HANDLE_DESC, this parameter value must be a connection handle.
OutputHandlePtr	Output parameter: Pointer to a buffer that stores the returned handle in the newly allocated data structure.

Return Value

SQL_SUCCESS indicates that the call succeeded.
SQL_SUCCESS_WITH_INFO indicates that some warning information is displayed.
SQL_ERROR indicates major errors, such as memory allocation and connection failures.
SQL_INVALID_HANDLE indicates that invalid handles were called. This value may also be returned by other APIs.

Precautions

If SQLAllocHandle returns SQL_ERROR when it is used to allocate a non-environment handle, it sets OutputHandlePtr to SQL_NULL_HDBC, SQL_NULL_HSTMT, or SQL_NULL_HDESC. The application can then call SQLGetDiagRec, with HandleType and Handle set to the value of IntputHandle, to obtain the SQLSTATE value. The SQLSTATE value provides the detailed function calling information.