database - SQL: Create new table or have redundant columns -


i have 6 tables: ajob, bjob, cjob, a, b , c.

  • ajob has n:1 dependency on a,
  • bjob has n:1 dependency on b and
  • cjob has n:1 dependency on c.

except dependencies (a|b|c)job tables same.

should create new table "jobs" , move same columns? (i have keep care of 1:1 dependency between "(a|b|c)job" , "jobs" , of entries in "jobs" when deleting "(a|b|c)job" )

or should keep design every jobtable has redundant columns?

(i have use "union" in subquery search , don't know if normalisation)

which 1 better practice?

if have same columns in multiple tables, don't need multiple tables. put in 1 table column differentiate a, b or c...

have read: https://en.wikipedia.org/wiki/database_normalization


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