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I have a column(dt) that either contains a date (mo/dd/yr) or a question mark(?). In my where close I'm trying to select only rows where the column has a question mark. I tried the following below and I get an error. 

where c.dt = '?'

The error I get is: SELECT Failed. 3535: A character string failed conversion to a numeric value.

ElGavilan
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1 Answers1

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The question mark is the string displayed for a NULL ;-)

E.g. this is the default in SQL Assistant and BTEQ.

So dt is actually a DATE column and you need to use:

where c.dt IS NULL

Btw, you can easily change that default:

  • BTEQ: .SET NULL 'whatever';
  • SQLA: Tools -> Options -> Data Format -> Display this string for NULL data values

I usually use <NULL> :)

dnoeth
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