insert.c

在VC6环境下开发

#include "eDbInit.h"
void eDbInsert(
	Parser *pParse,        /* Parser context */
	SrcList *pTabList,    /* Name of table into which we are inserting */
	ExprList *pList,      /* List of values to be inserted */
	Select *pSelect,      /* A SELECT statement to use as the data source */
	IdList *pColumn,      /* Column names corresponding to IDLIST. */
	int onError           /* How to handle constraint errors */
){
	Table *pTab;          /* The table to insert into */
	char *zTab;           /* Name of the table into which we are inserting */
	int i, j;			  /* Loop counters */
	int nColumn;          /* Number of columns in the data */
	eDb *db;			  /* The main database structure */
	int keyColumn = -1;   /* Column that is the INTEGER PRIMARY KEY */
	int isView;           /* True if attempting to insert into a view */

	ParseResult *pRes = eDbMalloc(sizeof(ParseResult));

	if( pParse->nErr || eDb_malloc_failed ) goto insert_cleanup;
	db = pParse->db;

	/* Locate the table into which we will be inserting new information.
	*/
	zTab = pTabList->a[0].zName;
	if( zTab==0 ) goto insert_cleanup;
	pTab = eDbSrcListLookup(pParse, pTabList);
	if( pTab==0 ){
		goto insert_cleanup;
	}
	isView = pTab->pSelect!=0;
	nColumn = pList->nExpr;
	for(i=0; i<nColumn; i++){
		if( eDbExprResolveIds(pParse, 0, 0, pList->a[i].pExpr) ){
			goto insert_cleanup;
		}
		if( eDbExprCheck(pParse, pList->a[i].pExpr, 0, 0) ){
			goto insert_cleanup;
		}
    }
	/* Make sure the number of columns in the source data matches the number
	** of columns to be inserted into the table.
	*/
	if( pColumn==0 && nColumn!=pTab->nCol ){
		eDbErrorMsg(pParse, 
		   "table %s has %d columns but %d values were supplied",
		   pTab->zName, 0, pTab->nCol, nColumn);
		goto insert_cleanup;
	}
	if( pColumn!=0 && nColumn!=pColumn->nId ){
		eDbErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
		goto insert_cleanup;
	}

	/* If the INSERT statement included an IDLIST term, then make sure
	** all elements of the IDLIST really are columns of the table and 
	** remember the column indices.
	*/
	if( pColumn ){
		for(i=0; i<pColumn->nId; i++){
			pColumn->a[i].idx = -1;
		}
		for(i=0; i<pColumn->nId; i++){
			/*find the column name in table and set its indices */
			for(j=0; j<pTab->nCol; j++){
				if( eDbStrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
					pColumn->a[i].idx = j;
					if( j==pTab->iPKey ){
						keyColumn = i;
					}
					break;
				}
			}
			if( j>=pTab->nCol ){
				eDbErrorMsg(pParse, "table %s has no column named %s",
				  pTab->zName, 0, pColumn->a[i].zName);
				pParse->nErr++;
				goto insert_cleanup;
			}
		} /* end for(i=0; i<pColumn->nId; i++)*/
	}/* end if(pColumn)*/

	/* If there is no IDLIST term but the table has an integer primary
	** key, the set the keyColumn variable to the primary key column index
	** in the original table definition.
	*/
	if( pColumn==0 ){
		keyColumn = pTab->iPKey;
	}   
	
	pRes->pTable = pTab;
	pRes->pIdList = pColumn;
	pRes->pEList = pList;
	pRes->op = Op_Insert;
	pParse->pResult = pRes;
	eDbSrcListDelete(pTabList);
	return;
insert_cleanup:
	eDbSrcListDelete(pTabList);
	if( pList ) eDbExprListDelete(pList);
	if( pSelect ) eDbSelectDelete(pSelect);
	eDbIdListDelete(pColumn);
}