MySQL Check existence of a set of fields in a table -


i validating existence of set of field values (eg: yyy,aaa , ccc) in table , using union gather results, prefer more elegant , efficient solution:

tablename: example_table

name | class 

xxx  | cse <br> yyy  | ee  <br> zzz  | mech <br> aaa  | cse  <br> bb   | cse <br>

my query:

select  if(name  null,"yyy ","")    example_table (name  '%yyy%')        union    (select  if(name  null,"aaa  ","")    example_table (name  '%aaa%'))        union    (select  if(name  null,"ccc ","")    example_table (name  '%ccc%'));

i need know of string values need not present in table. problem is, table using has around thousands of tuples , using union seems costly..

looking strings never elegant ;) if want shorten code, give in try. similar to...

...where name in ('yyy','aaa','ccc')....


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