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1.11.1.The syntax of the WHERE clause with an IN phrase
1.11.2.An IN phrase with a list of numeric literals
1.11.3.An IN phrase preceded by NOT
1.11.4.An IN phrase with a subquery
1.11.5.In and subquery
1.11.6.use subqueries to restrict what rows in a table will be deleted
1.11.7.An IN operator is equivalent to a series of conditions, connected with one or more OR operators.