Question

I am using sqlite database for store my data.But it is showing error of “database is locked” while insert query.Here is my code

 sqlite3_stmt    *statement;
        NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
        const char *dbpath = [[defaults objectForKey:@"dbpath"] UTF8String];

        if (sqlite3_open(dbpath, &studentDB22) == SQLITE_OK)
        {
            NSString *insertSQL = [NSString stringWithFormat:@"INSERT INTO Emotion_videos (name) VALUES (\"%@\")",filePath];
            const char *query_stmt = [insertSQL UTF8String];
                if (sqlite3_prepare_v2(studentDB22, query_stmt, -1, &statement, NULL) == SQLITE_OK)
                {
                    NSLog(@"shi h2345");
                    if (sqlite3_step(statement) == SQLITE_ROW)
                    {
                        printf( "could not prepare statement: %s\n", sqlite3_errmsg(studentDB22));

                    }

                }
            sqlite3_finalize(statement);
        }
        else
        {
                   printf( "could not prepare statement: %s\n", sqlite3_errmsg(studentDB22));
        }

I am able to insert data for two or three times but when it runs again,it shows database locked error.

Answer 1

You open the database but you don’t close it.

You shouldn’t use string formats to create queries. You should put ? placeholders in the query then bind the proper value. This takes care of things like properly quoting and escaping string values.

NSString *insertSQL = @"INSERT INTO Emotion_videos (name) VALUES (?)";

After you prepare the statement, call sqlite3_bind_text to bind the string value.

Also. don’t use sqlite3_open, use sqlite3_open_v2. It’s better and gives you more control.