sql server - Update a column of a table using another column of the same table -


i have 2 tables vehicle_table , vehicle_group_table

  • vehicle_table --> has columns --> vehicleid,groupname,groupid
  • vehicle_group_table --> has columns --> groupid,groupname

i want update vehicle_table's groupid column joining vehicle_group_table on common groupname column

update vehicle_table      set vehicle_table.groupid = vehicle_group_table.groupid     vehicle_table.groupname = vehicle_group_table.groupname

but seems not working.

update   v set   groupid = vg.groupid   vehicle_table v   join   vehicle_group_table vg on v.groupname = vg.groupname

you need correlate 2 tables via join. there other ways subqueries etc

note: don't use aliases in destination/target columns in set clause suggested in other answers. fails in sql server not in sql server 2012 think behaviour changed

for more complicated setup: sql update query using joins


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