SQL in iOS

To select data, methods like executeQuery can be used to return the FMResultSet object if successful, or 0 upon failure. There are methods, such as lastErrorMessage or lastErrorcode, to find out if the query has worked or failed:

FMResultSet *s = [db executeQuery:@"SELECT * FROM aTable"]; while ([s next]) {     //retrieve values for each record }

For multiple rows, [FMResultSet next] must be used to see or read the values returned from the query, even if the recordset is one, for example.

The following command shows how to use FMResultSet to select multiple queries as required:

FMResultSet *s = [db executeQuery:@"SELECT COUNT(*) FROM aTable"]; if ([s next]) {     int totalCount = [s intForColumnIndex:0]; }

FrmresultSet offers several methods to the programmer to retrieve; some examples are as follows:

• intForColumn:

• longForColumn:

• longLongIntForColumn:

Some of the aforementioned methods by default will have the {type}ForColumnIndex: variant, which will be used to get the data based on the...