oracle - Optimize where clause SQL -


i trying figure out way optimize below sql query:

select * some_table (col1 = 123 , col2 = 'abc')     or (col1 = 234 , col2 = 'cdf')    or (col1 = 755 , col2 = 'cvd') ---> have around 2000 'or' statements in single query.

currently query takes long time execute, there anyway make query run faster?

  • create lookup table create table lookup (col1 int, col2 varchar(3), primary key(col1, col2), key(col2)) organization index or whatever fits needs
  • make sure have indexes on original table (col1 , col2)
  • populate lookup table 2000 combinations

now query

select    mytable.* mytable inner join lookup on mytable.col1=lookup.col1 , mytable.col2=lookup.col2

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