# Zeos 8 fieldtype issues
**URL:** https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824
**Category:** Data Abstract
**Tags:** delphi
**Created:** [June 25, 2025, 7:33am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824 "2025-06-25T07:33:31Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@\_Koncz\_Timea](https://talk.remobjects.com/u/_Koncz_Timea)
#### Post date: [June 25, 2025, 7:33am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824/1 "2025-06-25T07:33:31Z")
Zeos driver older versions than 8.0 treated numericoid postgresql type as stDouble sql type (ZDbcPostgreSqlUtils.PostgreSQLToSQLType). In Zeos 8.0 is treated as stBigDecimal, resulting ftFMTBCD field type (result dataset field type), instead of ftDouble.
This issue causes wrong data conversion, for example, if on the server machine the decimal separator is “,” and on client machine is set to “.”.
Using an IDADataset resulted variant value type called with VarType results 258 (System.varUString - zeos 8) and 5 (System.varDouble - older than zeos 8).
Please check if you can adapt DA components or mark as a zeos issue.
---
### Author:  [@EvgenyK](https://talk.remobjects.com/u/EvgenyK)
#### Post date: [June 25, 2025, 7:44am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824/2 "2025-06-25T07:44:57Z")
Hi,
Can you create a DDL script that creates a table that reproduces this issue, pls?
I’ll review Zeos driver..
---
### Author:  [@\_Koncz\_Timea](https://talk.remobjects.com/u/_Koncz_Timea)
#### Post date: [June 25, 2025, 8:21am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824/3 "2025-06-25T08:21:02Z")
> [@EvgenyK](#):
>
> Can you create a DDL scri
On client side we running `SELECT CAST(3.7001 as decimal(15,4))`
On server side in ZDatasetUtils.pas, ConvertDatasetToDbcType function, changing result to ftBCD or ftFloat for stBigDecimal is our workaround (it was ftFmtBCD)
If you need something else, please tell me
---
### Author:  [@EvgenyK](https://talk.remobjects.com/u/EvgenyK)
#### Post date: [June 25, 2025, 10:41am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824/4 "2025-06-25T10:41:50Z")
Hi,
> [@\_Koncz\_Timea](#):
>
> On client side we running `SELECT CAST(3.7001 as decimal(15,4))`
in case of manual sql, as in your case, we detect datatypes according to Direct Access Component (= Zeos) information.
**Note** : you can change detected datatype to your own one in [Schema Modeler (Windows)](https://docs.dataabstract.com/Tools/SchemaModeler/Windows/).
in case of AutoSQL, we detect datatypes with `Postgres_DoGetTableFields` method.
* * *
another workaround - you can create own driver based on Zeos driver and override `intVCLTypeToDAType` method in `TDAEZeosQuery` class.
see example of it in `TDAEUniDACQuery.intVCLTypeToDAType`.
if you like this way, I can give more information how to create own driver based on existing Zeos driver.
---
### Author:  [@\_Koncz\_Timea](https://talk.remobjects.com/u/_Koncz_Timea)
#### Post date: [June 25, 2025, 10:49am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824/5 "2025-06-25T10:49:56Z")
> [@EvgenyK](#):
>
> `intVCLTypeToDAType`
We are running sql statements, so the schema modeler is not a solution.
`intVCLTypeToDAType` could be a solution.
I think that’s important to know about this, because others may struggle with the same problem.
Best regards
---
### Author:  [@EvgenyK](https://talk.remobjects.com/u/EvgenyK)
#### Post date: [June 25, 2025, 11:14am UTC](https://talk.remobjects.com/t/zeos-8-fieldtype-issues/31824/6 "2025-06-25T11:14:13Z")
Hi,
simple driver can be like
```auto
unit uMyZeosDriver;
...
type
TMyDAEZeosDriver = class (TDAEZeosDriver)
protected
function GetConnectionClass: TDAEConnectionClass; override;
end;
TMyDAEZeosConnection = class (TDAEZeosConnection)
protected
function GetDatasetClass: TDAEDatasetClass; override;
end;
TMyDAEZeosQuery = class(TDAEZeosQuery)
protected
function intVCLTypeToDAType(aFieldType: TFieldType; ASize: Integer = 0; ADecimalPrecision: Integer = 0; aDecimalScale: Integer = 0): TDADataType; override;
end;
function GetDriverObject: IDADriver; stdcall;
implementation
function TMyDAEZeosDriver.GetConnectionClass: TDAEConnectionClass;
begin
Result := TMyDAEZeosConnection;
end;
function TMyDAEZeosConnection.GetDatasetClass: TDAEDatasetClass;
begin
Result := TMyDAEZeosQuery;
end;
function TMyDAEZeosQuery.intVCLTypeToDAType(aFieldType: TFieldType; ASize,
ADecimalPrecision, aDecimalScale: Integer): TDADataType;
begin
case aFieldType of
....
else
Result := inherited intVCLTypeToDAType(aFieldType, ASize, ADecimalPrecision, aDecimalScale);
end;
end;
function GetDriverObject: IDADriver;
begin
if (_driver = nil) then _driver := TMyDAEZeosDriver.Create(nil);
result := _driver;
end;
initialization
_driver := nil;
UnregisterDriverProc(uDAZeosDriver.GetDriverObject);
RegisterDriverProc(GetDriverObject);
finalization
UnregisterDriverProc(GetDriverObject);
FreeAndNIL(_driver);
end.
```
**Note** : if you need custom similar support in Stored procedures, you should create descendant of `TDAEZeosStoredProcedure`, override `intVCLTypeToDAType` in it and register that descendant with `GetStoredProcedureClass` similar to query.
* * *
usage: you should include `uMyZeosDriver` to your server data module instead of `uZeosDriver`.