sql - How to "collapse" rows? -


so, if current resultset is:

 set  |  label  |  val ------------------------     |  "laba" |  null     |  "laba" |   1     |  "labb" |  null     |  "labb" |   2   b   |  "laba" |  null   b   |  "laba" |   3   b   |  "labc" |  null

what want is:

 set  |  label  |  val ------------------------     |  "laba" |   1     |  "labb" |   2   b   |  "laba" |   3   b   |  "labc" |  null

how can "collapse" rows desired resultset?

you need max() aggregate group by on set , label columns:

select  set, label, max(val) val    yourtable group set, label order set, label

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