select * from table_test t where t.field like '%aa%'

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select * from table_test t where instr('aa',t.field )>0

如果字段不确定,就需要全文索引


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探讨

select * from table_test t where instr('aa',t.field )>0 

如果字段不确定,就需要全文索引 


------解决方案--------------------
就like就行了
select * from table_test t where t.field like '%aa%'


------解决方案--------------------

探讨

SQL code
select * from table_test t where t.field like '%aa%'



模糊查询，所有的数据库都一样


------解决方案--------------------
select * from table_test t where t.field like '%aa%'