从数据库中插入值

Question

我将带有文本的坐标值插入数据库。当我从数据库中检索值时，它没有得到。我使用NSLog检索值，但nslog坐标值为0. getmainsql is SELECT textnotes,text_id,txcoor,tycoor FROM textnote where text_id = '159' AND txcoor = '0.000000' AND tycoor = '0.000000'

插入：

if (sqlite3_open([path UTF8String], &database) == SQLITE_OK) {
       const char *sql = [[NSString stringWithFormat:@"SELECT textnotes,text_id,txcoor,tycoor FROM textnote where textnotes = '%@' AND text_id = '%@' AND txcoor = '%f' AND tycoor = '%f'",txtview.text,artID,xcor,ycor] cStringUsingEncoding:NSUTF8StringEncoding];

        NSLog(@"sql is %s",sql);

        BOOL favExist = false;

        sqlite3_stmt *statement, *addStmt;

        if (sqlite3_prepare_v2(database, sql, -1, &statement, NULL) == SQLITE_OK) {
            // We "step" through the results - once for each row.
            while (sqlite3_step(statement) == SQLITE_ROW) {


                favExist = true;
            }
        }


        if(!favExist){


            const char *sqlInsert = [[NSString stringWithFormat:@"insert into textnote (textnotes,text_id,txcoor,tycoor ) values ('%@','%@','%f','%f')", txtview.text,artID,xcor,ycor] cStringUsingEncoding:NSUTF8StringEncoding];

            NSLog(@"sql insert is %s",sqlInsert);

            // [catID release];

            if(sqlite3_prepare_v2(database, sqlInsert, -1, &addStmt, NULL) != SQLITE_OK)
                NSAssert1(0, @"Error while creating add statement. '%s'", sqlite3_errmsg(database));

            if(SQLITE_DONE != sqlite3_step(addStmt))
                NSAssert1(0, @"Error while inserting data. '%s'", sqlite3_errmsg(database));

.h文件：

@property(nonatomic) float a;
@property(nonatomic) float b;

获得价值：

const char *sql = [[NSString stringWithFormat:@"SELECT textnotes,text_id,txcoor,tycoor FROM textnote where  text_id = '%@' AND txcoor = '%f' AND tycoor = '%f'",artID,a,b] cStringUsingEncoding:NSUTF8StringEncoding];


        NSLog(@"getmainsql is %s",sql);

        sqlite3_stmt *statement;

        if (sqlite3_prepare_v2(database, sql, -1, &statement, NULL) == SQLITE_OK) {
            // We "step" through the results - once for each row.
            while (sqlite3_step(statement) == SQLITE_ROW) {

                 xff=sqlite3_column_double(statement, 2);

                yff=sqlite3_column_double(statement, 3);

                art_Id = sqlite3_column_int(statement, 1);

                NSLog(@"xff is %f",xff);

                NSLog(@"yff is %f",yff);

                //  NSLog(@"zc is %@",zc);

                NSLog(@"art_Id is %ld",(long)art_Id);