function TPDO.query_as_is (sql: AnsiString): IPDOStatement;

TPDO.query_as_is executes an SQL statement in a single function call, returning the result set (if any) returned by the statement as a PDOStatement object.

For a query that you need to issue multiple times, you will realize better performance if you prepare an IPDOStatement object using TPDO.prepare_as_is or TPDO.prepare_select and issue the statement with multiple calls to IPDOStatement.execute after binding.

If you do not fetch all of the data in a result set before issuing your next call to TPDO::query_as_is or TPDO::query_select, there should not be any problem. Any remaining result is freed before another query is sent to the database server.

Parameters

sql: The SQL statement to prepare and execute.

Return Values

TPDO.query returns a IPDOStatement object.

Example

A nice feature of TPDO.query_as_id is that it enables you to iterate over the rowset returned by a successfully executed SELECT statement.

procedure example;
Begin
  {stmt and db are global IPDOStatement and TPDO objects}
  {row is a global TPDORowNative object}

  stmt := db.query_as_is ('SELECT name, colour, calories FROM fruit ORDER BY name');
  while (stmt.fetch(row)) do 
       writeln (
           row.hash('name').asString + chr(9) + 
           row.hash('colour').asString + chr(9) + 
           row.hash('calories').asString
       );
end;

The above example will output:

apple   red     150
banana  yellow  250
kiwi    brown   75
lemon   yellow  25
orange  orange  300
pear    green   150
watermelon      pink    90

The difference between TPDO.query_as_is and TPDO.query_select is that the former accepts the query as a string, which can be anything, and the later accepts 6 components so that it can assembly a SELECT statement as a function of which the connected database server.