Does the include order has any impact on covering indexes?

Question

Is there any difference between the two following indexes in PostgreSQL:

CREATE INDEX my_index ON table_name (column_one, column_two)
   INCLUDE (account_id, id)

and

CREATE INDEX my_index ON table_name (column_one, column_two)
   INCLUDE (id, account_id)

The order of the columns in your index (column_one, column_two) is *CRITICAL*. The order of the columns in your (optional!) "INCLUDE" clause doesn't matter. For an excellent discussion of the hows/whys, look here: [A Close Look at the Index Include Clause](https://use-the-index-luke.com/blog/2019-04/include-columns-in-btree-indexes). — FoggyDay, Jun 05 '20 at 20:10

score 2 · Accepted Answer · answered Jun 05 '20 at 19:59

2

No, there is no difference in behavior between these two indexes. The order in the INCLUDE list does not matter.

answered Jun 05 '20 at 19:59

Laurenz Albe

1 Answers1