mysql - query "not equal" doesn't work -

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mysql - query "not equal" doesn't work -

i have simple query this:

select * `all_conversations` `deleted_1` != '1';

and deleted_1 default null or user id, reason query returns me 0 rows, tried <> still no luck wrong?

edti after running more querys find out problems default value of deleted_1 field, null modified query , works fine:

select * `all_conversations` `deleted_1` != 'null' , `deleted_1` != 23

select * all_conversations deleted_1 <> 1 or deleted_1 null

null values need special treatment: http://dev.mysql.com/doc/refman/5.1/en/working-with-null.html

i'd suggest using diamond operator (<>) in favor of != first 1 valid sql , sec 1 mysql addition.

mysql sql

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