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Howdy!

I have a calculated BOOLEAN column that I want to return with a SELECT set. Since BOOLEANs are stored as INTEGERs, the values are 0 for False and 1 for True.

That is,

SELECT <field 1>,<field 2>,0 AS Enabled
FROM <Table>

When I get the result set from TVirtualQuery and I try to copy the results to a TkbmMemTable, I am getting an error on the BOOLEAN field in the TkbmMemTable that 0 is NOT valid Boolean value for column 'Enabled'.

Any suggestions on how to fix this? All actual table boolean columns work fine.

All the best,

Aggie85

Thank you for the information. Unfortunately, we could not reproduce the problem according to your description. Please compose and send us via the e-support form (https://www.devart.com the "Support"\"Request Support" menu) a small complete sample in which the problem occurs.

Good day Maxim!

The problem is the constant field I am adding in the SELECT statement returns fine from TVirtualQuery, but when I try to copy the returned data to a TkbmMemTable dataset, I get the error.

I have even tried

SELECT <field 1>,<field 2>,(CAST 0 AS BOOLEAN) AS Enabled
FROM <Table>

And I get the same error. How can I get TVirtualQuery to make sure Enabled is a BOOLEAN in the return dataset (the field doesn't exist in any underlying dataset in the SELECT - it is a calculated field for the resulting dataset the data will be copied into).

Thanks,

Aggie85

To execute the described queries using VirtualQuery, you can use DataTypeMapping. For this, before opening the query, create the following rule :

I will add it to my framework for special occasions when needed.

Thanks,

Aggie85

The TVirtualQuery's DataTypeMap did the trick.

Thanks,

Aggie85

We are glad that we could find the solution, which helped to implement your projects.

Most thanks!

All the best,

Aggie85