Delphi DBExpress SQLDataSet.ExecSQL freezes

Question

I am comparing BDE and DBExpress components and try to execute simple update in TMPTABLE.

When I use BDE TQuery Query.ExecSQL works fine, but if I use DBExpress TSQLDataSet, it freezes in SQLDataSet.ExecSQL.

I use Delphi XE3 in Win7 64b. Database is Oracle.
BDE Query uses ODBC-connection, but DBExpress SQLDataSet uses Oracle driver.

What is wrong with this?

procedure Test;
var
  Query      : TQuery;       // dbe 
  SQLDataSet : TSQLDataSet;  // dbexpress 
begin  
  Query := TQuery.Create(nil);   
  Query.DatabaseName := 'DatabaseName';  
  Query.SQL.Add('update TMPTABLE set STATUS = 1');  
  Query.ExecSQL; // <-- OK  
  Query.Free;  

  SQLDataSet := TSQLDataSet.Create(nil);  
  SQLDataSet.SQLConnection := SQLConnection;  
  SQLDataSet.CommandType   := ctQuery;  
  SQLDataSet.CommandText   := 'update TMPTABLE set STATUS = 1';  
  SQLDataSet.ExecSQL;  // <-- Freezes here  
  SQLDataSet.Free;  
end;

These are SQLConnection Params:

DriverUnit=Data.DBXOracle
DriverPackageLoader=TDBXDynalinkDriverLoader,DBXCommonDriver170.bpl
 DriverAssemblyLoader=Borland.Data.TDBXDynalinkDriverLoader,Borland.Data.DbxCommonDriver,Version=17.0.0.0,Culture=neutral,PublicKeyToken=91d62ebb5b0d1b1b
MetaDataPackageLoader=TDBXOracleMetaDataCommandFactory,DbxOracleDriver170.bpl
MetaDataAssemblyLoader=Borland.Data.TDBXOracleMetaDataCommandFactory,Borland.Data.DbxOracleDriver,Version=17.0.0.0,Culture=neutral,PublicKeyToken=91d62ebb5b0d1b1b
GetDriverFunc=getSQLDriverORACLE
LibraryName=dbxora.dll
LibraryNameOsx=libsqlora.dylib
VendorLib=oci.dll
VendorLibWin64=oci.dll
VendorLibOsx=libociei.dylib
DataBase=Database Name
User_Name=user
Password=password
MaxBlobSize=-1
LocaleCode=0000
IsolationLevel=ReadCommitted
RowsetSize=20
OSAuthentication=False
MultipleTransactions=False
TrimChar=False
BlobSize=-1
ErrorResourceFile=
OS Authentication=False
Multiple Transaction=False
Trim Char=False
Decimal Separator=.

It freezes. I have to reset debugging. What debug do you mean? — pKarelian
Can you retrieve records via select, and then do a SQLDataSet.Open? maybe you have problems with your provider/driver. — kobik
Select gives dataset. Connection to database is ok. I tried DbGo component too but update fails again. BDE component works fine. — pKarelian
Assuming dbExpress has source code provided, enable DebugDCUs and step into the execSQL (and into functions therein) to find out what line it's actually freezing on. This will give a better clue as to what is going on — Matt Allwood
Usually T[SQL]DataSet is not used in conjunction with ExecSQL. try to use TSQLQuery. I know it's a long-shot because TSQLDataSet should also work... — kobik

pKarelian pKarelian · Accepted Answer · 2014-01-21T05:55:21

I finally understood what was wrong with this. Example was too simple. I didn't see that there was already bde transaction running like this.

DataBase.StartTransaction; // BDE StartTansaction 

BDEQuery.ExecSQL;       // <-- BDE update OK  
SQLDataSet.ExecSQL;     // <-- DBX update Freezes, because it waits for bde commit  

DataBase.Commit;        //  BDE Commit

Delphi DBExpress SQLDataSet.ExecSQL freezes

1 Answers