indexing - Indexes on tables -


i wrote query in db2 uses inner join on 4 tables. created index 4 columns on fourth table in same order columns being accessed in clause of query. index had created not being used when check performance of query using explain. faced similar issue or know reason this?

let a,b,c,d tables , d1,d2,d3,d4 columns of table-d. in clause conditions a1=d1,b1=d2,c1=d3,c2=d4(a1,b1,c1 columns in tables a,b,c). , index on table-d "create index index_name on table_name (d1,d2,d3,d4);"


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