mysql - How to update table, with selected values from another table -

i want update field tag in accountinfo table value abcd results of select query in diferent table of same db. query doesn't return errors, neither update.

update accountinfo   set tag= 'abcd'  'abcd%' in (select name hardware name 'abcd%'); 

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select name hardware name 'abcd%'  abcdabelchior abcdabelmarques abcdag200cx1 

the in operator equality comparison. use of '%' in string literal makes if want sort of like comparsion... matching first 4 characters.

the predicate in where clause of query going evaluate either true or false, every in accountinfo table, no matter row in accountinfo contains. you're either going update none of rows, or all of rows.

which rows in accountinfo want update?

is there "matching" of rows in accountinfo rows in hardware? how going know if rows "match"?

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edit:

there no rows match accountinfo in hardware.

so, information have go on: there's column named tag in accountinfo table. , that's column know about.

there column named name in hardware table. , there rows in table name values begin 'abcd'.

again, which rows in accountinfo did want update? how going identify rows update?