TClientDataSet and big insert

Question

In my application I use TADOQuery with select (MSSQL) and linked with it TClientDataSet. I have to insert about million records and ApplyUpdates.

So what I see in the SQL Server Profiler? I see that for each inserted row we have 3 queries: sp_prepare of insert script, sp_execute it with some values and sp_unprepare.

I want just to prepare sql once for all of the records before insert and unprepare it after. How can I do it?

Added after:

In the query I have a script for the stored procedure execution:

tmpQuery := DefineQuery(FConnection, [
  'exec up_getOperatorDataSet ',
  '  @tablename     = :tablename, ',
  '  @operator      = :operator, ',
  '  @forappend     = :forappend, ',
  '  @withlinksonly = :withlinksonly, ',
  '  @ids           = :ids '
], [
  Param(ftString, sTableName),
  Param(ftInteger, FOperatorId),
  Param(ftBoolean, opForAppendOnly in OpenParams),
  Param(ftBoolean, opOnlyWithModelLinks in OpenParams),
  Param(ftString, sIds)
], Result);

It selects all of the fields from table sTableName with some parameters.

Example of inserting from profiler:

step 1:

declare @p1 int
set @p1=486
exec sp_prepare @p1 output,N'@P1 int,@P2 int,@P3 datetime,@P4 int,@P5 int,@P6 int,@P7 int,@P8 int,@P9 varchar(128),@P10 bit,@P11 numeric(19,4),@P12 smallint,@P13 smallint,@P14 smallint,@P15 smallint',N'insert into parser_prices
  (operator_id, request_id, date, nights, model_hotel_id, model_meal_id, model_room_id, model_htplace_id, spo, hotelstop, price, frout_econom, frout_business, frback_econom, frback_business)
values
  (@P1, @P2, @P3, @P4, @P5, @P6, @P7, @P8, @P9, @P10, @P11, @P12, @P13, @P14, @P15)
',1
select @p1

step 2:

exec sp_execute 486,21,2000450,'2009-12-04 00:00:00',14,2118,22,-9555,18,'2009-10.MSK.Bali.13.10.09-27.03.10',0,15530.0000,3,3,3,3

step 3:

exec sp_unprepare 486

and it is for all of the new rows.

Answer 1

Because you're calling a stored procedure, and not an inline query in your code, then SQL Server is treating each call to the stored proc as a separate call, and so is preparing it and unpreparing it every time. I'm not sure if there is a way around this.

If whatever is happening within the stored proc can be done from a query in your code, then you could use a structure like this that would only prepare the SQL statement the first time:

{Prepare the insert query}
ADOQuery1.SQL.Append('INSERT INTO Tablename');
ADOQuery1.SQL.Append('(StringField1, IntField2)');             {repeat as necessary}
ADOQuery1.SQL.Append('VALUES (:sFieldValue1, :sFieldValue2)'); {repeat as necessary}
ADOQuery1.SQL.Prepare;

{In a For, While, Repeat loop, use:}
ADOQuery1.ParamByName('sFieldValue1').AsString := 'Value for field 1';
ADOQuery1.ParamByName('sFieldValue2').AsInteger := 2;
ADOQuery1.ExecSQL;

Apologies if I've not quite got the property and method names right for the ADOQuery component, I'm not on my Delphi PC at the moment and I don't usually use the TADO components, but the concept still applies as this is a TDataSet concept.