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I am porting an application to work with both Oracle and SQL Server. It seems like the best approach is to move from ODAC to UniDac, but I have hit a problem.

I am getting EDatabaseError ... Type mismatch for field '<fieldname>", expecting: Float actual: LargeInt.

I can't just change all my Float fields to LargeInts because some of the Floats are Actually floats.

Why does this problem exist and what do you suggest I do about it?

Note that some of the Float fields are integers, but when adding them in the BDE or ODAC they come up automatically as Float fields.

Hello,

This behavior is due to different definition of field types in ODAC and UniDAC depending on the field size in a database.
To solve the issue, you should set mapping rules for the needed fields. For example, in ODAC, a NUMBER(18, 0) field in the database will be defined as TFloatField, and in UniDAC - as TLargeintField. To make behavior identical, set the following rule:
or set it in the UniQuery edit form on the DataTypeMapping tab.

Thanks Alex.

Must I do this for each field, or can I do it once for each application?

Regards
David

Hi Alex

I found this

fAADataBase.DataTypeMap.AddDBTypeRule(oraNumeric, 11, rlAny, 0, 0, ftLargeint);

Can I use if for the database?

but where are OrNumeric, rlAny and ftLargeInt defined?

Regards
David

PS:
Here is my code:

TBaseDataObjectDAC = Class (TInterfacedObject)
private
{ Private Declarations }

fAADataBase: TUniConnection;
...


if not Assigned(fAADatabase) then
begin
fAADataBase:= TUniConnection.Create( nil );
fAADataBase.DataTypeMap.AddDBTypeRule(oraNumeric, 11, rlAny, 0, 0, ftLargeint);
//UniTable1.DataTypeMap.AddDBTypeRule(oraNumber, ftFloat, 18);
end;

To apply mapping rules "globally", you should set them in TUniConnection - then the rule will be applied to all DataSets related to this UniConnection.
The oraNumber type is declared in the OraDataTypeMapUni module, the rlAny type - in MemDS, the ftLargeint type - in the DB.

Thanks Alex.

At the moment I am changing the relevant types to LongInts where applicable.

I'll keep you posted as to my progress.

Regards
David

You are welcome. Feel free to contact us if you have any further questions.