sqldescribecol.c

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/*
 * The contents of this file are subject to the MonetDB Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://monetdb.cwi.nl/Legal/MonetDBLicense-1.1.html
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
 * License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is the MonetDB Database System.
 *
 * The Initial Developer of the Original Code is CWI.
 * Portions created by CWI are Copyright (C) 1997-2007 CWI.
 * All Rights Reserved.
 */

/*
 * This code was created by Peter Harvey (mostly during Christmas 98/99).
 * This code is LGPL. Please ensure that this message remains in future
 * distributions and uses of this code (thats about all I get out of it).
 * - Peter Harvey [e-mail]
 * 
 * This file has been modified for the MonetDB project.  See the file
 * Copyright in this directory for more information.
 */

/**********************************************************************
 * SQLDescribeCol()
 * CLI Compliance: ISO 92
 *
 * Author: Martin van Dinther
 * Date  : 30 aug 2002
 *
 **********************************************************************/

#include "ODBCGlobal.h"
#include "ODBCStmt.h"
#include "ODBCUtil.h"


static SQLRETURN
SQLDescribeCol_(ODBCStmt *stmt, SQLUSMALLINT nCol, SQLCHAR *szColName, SQLSMALLINT nColNameMax, SQLSMALLINT *pnColNameLength, SQLSMALLINT *pnSQLDataType, SQLUINTEGER *pnColSize, SQLSMALLINT *pnDecDigits, SQLSMALLINT *pnNullable)
{
	ODBCDescRec *rec = NULL;

	/* check statement cursor state, query should be executed */
	if (stmt->State == INITED) {
		/* Function sequence error */
		addStmtError(stmt, "HY010", NULL, 0);
		return SQL_ERROR;
	}
	if (stmt->State == PREPARED0) {
		/* Prepared statement not a cursor-specification */
		addStmtError(stmt, "07005", NULL, 0);
		return SQL_ERROR;
	}
	if (stmt->State == EXECUTED0) {
		/* Invalid cursor state */
		addStmtError(stmt, "24000", NULL, 0);
		return SQL_ERROR;
	}

	if (nCol < 1 || nCol > stmt->ImplRowDescr->sql_desc_count) {
		/* Invalid descriptor index */
		addStmtError(stmt, "07009", NULL, 0);
		return SQL_ERROR;
	}

	rec = stmt->ImplRowDescr->descRec + nCol;

	/* now copy the data */
	copyString(rec->sql_desc_name, szColName, nColNameMax, pnColNameLength, SQLSMALLINT, addStmtError, stmt);

	if (pnSQLDataType)
		*pnSQLDataType = rec->sql_desc_concise_type;

	/* also see SQLDescribeParam */
	if (pnColSize)
		*pnColSize = ODBCDisplaySize(rec);

	/* also see SQLDescribeParam */
	if (pnDecDigits) {
		switch (rec->sql_desc_concise_type) {
		case SQL_DECIMAL:
		case SQL_NUMERIC:
			*pnDecDigits = rec->sql_desc_scale;
			break;
		case SQL_BIT:
		case SQL_TINYINT:
		case SQL_SMALLINT:
		case SQL_INTEGER:
		case SQL_BIGINT:
			*pnDecDigits = 0;
			break;
		case SQL_TYPE_TIME:
		case SQL_TYPE_TIMESTAMP:
		case SQL_INTERVAL_SECOND:
		case SQL_INTERVAL_DAY_TO_SECOND:
		case SQL_INTERVAL_HOUR_TO_SECOND:
		case SQL_INTERVAL_MINUTE_TO_SECOND:
			*pnDecDigits = rec->sql_desc_precision;
			break;
		}
	}

	if (pnNullable)
		*pnNullable = rec->sql_desc_nullable;

	return stmt->Error ? SQL_SUCCESS_WITH_INFO : SQL_SUCCESS;
}

SQLRETURN SQL_API
SQLDescribeCol(SQLHSTMT hStmt, SQLUSMALLINT nCol, SQLCHAR *szColName, SQLSMALLINT nColNameMax, SQLSMALLINT *pnColNameLength, SQLSMALLINT *pnSQLDataType, SQLUINTEGER *pnColSize, SQLSMALLINT *pnDecDigits, SQLSMALLINT *pnNullable)
{
	ODBCStmt *stmt = (ODBCStmt *) hStmt;

#ifdef ODBCDEBUG
	ODBCLOG("SQLDescribeCol " PTRFMT " %d\n", PTRFMTCAST hStmt, nCol);
#endif

	if (!isValidStmt(stmt))
		 return SQL_INVALID_HANDLE;

	clearStmtErrors(stmt);

	return SQLDescribeCol_(stmt, nCol, szColName, nColNameMax, pnColNameLength, pnSQLDataType, pnColSize, pnDecDigits, pnNullable);
}

#ifdef WITH_WCHAR
SQLRETURN SQL_API
SQLDescribeColA(SQLHSTMT hStmt, SQLUSMALLINT nCol, SQLCHAR *szColName, SQLSMALLINT nColNameMax, SQLSMALLINT *pnColNameLength, SQLSMALLINT *pnSQLDataType, SQLUINTEGER *pnColSize, SQLSMALLINT *pnDecDigits, SQLSMALLINT *pnNullable)
{
	return SQLDescribeCol(hStmt, nCol, szColName, nColNameMax, pnColNameLength, pnSQLDataType, pnColSize, pnDecDigits, pnNullable);
}

SQLRETURN SQL_API
SQLDescribeColW(SQLHSTMT hStmt, SQLUSMALLINT nCol, SQLWCHAR * szColName, SQLSMALLINT nColNameMax, SQLSMALLINT *pnColNameLength, SQLSMALLINT *pnSQLDataType, SQLUINTEGER *pnColSize, SQLSMALLINT *pnDecDigits, SQLSMALLINT *pnNullable)
{
	ODBCStmt *stmt = (ODBCStmt *) hStmt;
	SQLCHAR *colname;
	SQLSMALLINT n;
	SQLRETURN rc = SQL_ERROR;

#ifdef ODBCDEBUG
	ODBCLOG("SQLDescribeColW " PTRFMT " %d\n", PTRFMTCAST hStmt, nCol);
#endif

	if (!isValidStmt(stmt))
		 return SQL_INVALID_HANDLE;

	clearStmtErrors(stmt);

	prepWcharOut(colname, nColNameMax);

	rc = SQLDescribeCol_(stmt, nCol, colname, nColNameMax * 4, &n, pnSQLDataType, pnColSize, pnDecDigits, pnNullable);

	fixWcharOut(rc, colname, n, szColName, nColNameMax, pnColNameLength, 1, addStmtError, stmt);

	return rc;
}
#endif /* WITH_WCHAR */