Re: NOT IN is very inefficient

On 10 Oct 1998 00:36:07 GMT, jamesc_at_zip.com.au (James Cribb) wrote:

>[Following up my own post...]
>
>In article <6vi8r9$bd9$1_at_nnrp1.dejanews.com>, jamesc7704_at_my-dejanews.com wrote:
>| In article <360ce23e.31649562_at_newslist>, skoterski_at_NOSPAMinprise.com wrote:
>| >
>| > SELECT T1.my_field
>| > FROM my_table1 T1
>| > LEFT OUTER JOIN my_table2 T2
>| > ON (T1.my_field = T2.my_field)
>| > WHERE (T2.my_field IS NULL)
>|
>| I tried this in Sybase SQL Anywhere, but it didn't work.
>
>Mea culpa. The query above DOES work in SQL Anywhere.
>I had not seen the above syntax for outer joins before
>and was instead using the syntax I was familiar with.

The syntax I posted is (supposed to be) universal. It is from the SQL-92 specification. The "*=" operator is a nonstandard extension to the language. Most database systems that include nonstandard syntax will typically also still support standard syntax, as you have seen.

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