Need help with conversion

Hakan Axheim

8y1.1k

Hi,

I am trying to make better performance in our sql statements. We have problems with som queries that has slow performance. It seems regarding to the sql server estimated execution plan that the problem is implicit conversion.

This is my query;

select abbreviation + CONVERT(varchar(23), beginTimestamp, 121) as partof

from customer

abbreviation is a varchar field

beginTimestamp is a timestamp

and those two fields I wan't to concatenate in to one field.

In estimated execution plan I got a warning that says: type conversion in expression (CONVERT (varchar(23), beginTimestamp, 121) may affect CardinalityEstimate in query plan choise.

Maybee some one can help me with this!

3 Replies

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Sumit Chaudhary8y ago
try this below link

https://docs.microsoft.com/en-us/sql/t-sql/functions/current-timestamp-transact-sql

hope this is helpfull for you.
Hakan Axheim8y ago
I'm sorry but it doesn't seems to be better. I tested your suggestion but I got a warning that says: type conversion in expression (CONVERT (varchar(20), beginTimestamp) may affect CardinalityEstimate in query plan choice.

It seems that sql server does implicit conversion and I don't want sql server to do implicit conversion.
Sumit Chaudhary8y ago
Try this

select abbreviation + cast(beginTimestamp as varchar(10)) as partof from customer