Substract Dates in FirebirdSQL 1.5 Dialect 3

Hi there All!


I was trying to Benchmark a Stored Procedure 'cause it sent me recordset in very different times, So I tried to Get a

TIEMPO_INICIAL= CAST(CURRENT_TIMESTAMP AS TIMESTAMP);

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TIEMPO_FINAL= CAST(CURRENT_TIMESTAMP AS TIMESTAMP);

When I tried to do this:

TIEMPO_RESULTANTE = (TIEMPO_FINAL) - (TIEMPO_INICIAL);

It sends me an error:

CONVERSION ERROR FROM STRING 0.0000000
....

Where could I find Dates Handling documentation?

Am I wrong?

I aprecciate!
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