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SQLNativeSql Function

Conformance
Version Introduced: ODBC 1.0 Standards Compliance: ODBC

Summary
SQLNativeSql returns the SQL string as modified by the driver. SQLNativeSql does not execute the SQL statement.

Syntax

  
SQLRETURN SQLNativeSql(  
     SQLHDBC        ConnectionHandle,  
     SQLCHAR *      InStatementText,  
     SQLINTEGER     TextLength1,  
     SQLCHAR *      OutStatementText,  
     SQLINTEGER     BufferLength,  
     SQLINTEGER *   TextLength2Ptr);  

Arguments

ConnectionHandle
[Input] Connection handle.

InStatementText
[Input] SQL text string to be translated.

TextLength1
[Input] Length in characters of *InStatementText text string.

OutStatementText
[Output] Pointer to a buffer in which to return the translated SQL string.

If OutStatementText is NULL, TextLength2Ptr will still return the total number of characters (excluding the null-termination character for character data) available to return in the buffer pointed to by OutStatementText.

BufferLength
[Input] Number of characters in the *OutStatementText buffer. Past versions of this documentation mistakenly implied that this count of characters must be even if the value returned in *InStatementText is a Unicode string (when calling SQLNativeSqlW). There is no such a restriction. For optimal interoperability, driver writers should expect any count of characters to be passed to this function, while application writers are recommended to always use an even count.

TextLength2Ptr
[Output] Pointer to a buffer in which to return the total number of characters (excluding null-termination) available to return in *OutStatementText. If the number of characters available to return is greater than or equal to BufferLength, the translated SQL string in *OutStatementText is truncated to BufferLength minus the length of a null-termination character.

Returns

SQL_SUCCESS, SQL_SUCCESS_WITH_INFO, SQL_ERROR, or SQL_INVALID_HANDLE.

Diagnostics

When SQLNativeSql returns either SQL_ERROR or SQL_SUCCESS_WITH_INFO, an associated SQLSTATE value can be obtained by calling SQLGetDiagRec with a HandleType of SQL_HANDLE_DBC and a Handle of ConnectionHandle. The following table lists the SQLSTATE values commonly returned by SQLNativeSql and explains each one in the context of this function; the notation "(DM)" precedes the descriptions of SQLSTATEs returned by the Driver Manager. The return code associated with each SQLSTATE value is SQL_ERROR, unless noted otherwise.

SQLSTATE Error Description
01000 General warning Driver-specific informational message. (Function returns SQL_SUCCESS_WITH_INFO.)
01004 String data, right truncated The buffer *OutStatementText was not large enough to return the entire SQL string, so the SQL string was truncated. The length of the untruncated SQL string is returned in *TextLength2Ptr. (Function returns SQL_SUCCESS_WITH_INFO.)
08003 Connection not open The ConnectionHandle was not in a connected state.
08S01 Communication link failure The communication link between the driver and the data source to which the driver was connected failed before the function completed processing.
22007 Invalid datetime format *InStatementText contained an escape clause with an invalid date, time, or timestamp value.
24000 Invalid cursor state The cursor referred to in the statement was positioned before the start of the result set or after the end of the result set. This error may not be returned by a driver having a native DBMS cursor implementation.
HY000 General error An error occurred for which there was no specific SQLSTATE and for which no implementation-specific SQLSTATE was defined. The error message returned by SQLGetDiagRec in the *MessageText buffer describes the error and its cause.
HY001 Memory allocation error The driver was unable to allocate memory required to support execution or completion of the function.
HY009 Invalid use of null pointer (DM) *InStatementText was a null pointer.
HY010 Function sequence error (DM) An asynchronously executing function was called for the ConnectionHandle and was still executing when this function was called.
HY013 Memory management error The function call could not be processed because the underlying memory objects could not be accessed, possibly because of low memory conditions.
HY090 Invalid string or buffer length (DM) The argument TextLength1 was less than 0, but not equal to SQL_NTS.
(DM) The argument BufferLength was less than 0 and the argument OutStatementText was not a null pointer.
HY109 Invalid cursor position The current row of the cursor had been deleted or had not been fetched. This error may not be returned by a driver having a native DBMS cursor implementation.
HY117 Connection is suspended due to unknown transaction state. Only disconnect and read-only functions are allowed. (DM) For more information about suspended state, see SQLEndTran Function.
HYT01 Connection timeout expired The connection timeout period expired before the data source responded to the request. The connection timeout period is set through SQLSetConnectAttr, SQL_ATTR_CONNECTION_TIMEOUT.
IM001 Driver does not support this function (DM) The driver associated with the ConnectionHandle does not support the function.

Comments

The following are examples of what SQLNativeSql might return for the following input SQL string containing the scalar function CONVERT. Assume that the column empid is of type INTEGER in the data source:

SELECT { fn CONVERT (empid, SQL_SMALLINT) } FROM employee  

A driver for Microsoft SQL Server might return the following translated SQL string:

SELECT convert (smallint, empid) FROM employee  

A driver for ORACLE Server might return the following translated SQL string:

SELECT to_number (empid) FROM employee  

A driver for Ingres might return the following translated SQL string:

SELECT int2 (empid) FROM employee  

For more information, see Direct Execution and Prepared Execution.

None.

See Also

ODBC API Reference
ODBC Header Files