The index is a B-Tree, not hashed. The order of the segments of the key
makes a big difference to queries, as pointed out earlier. It doesn't
make any significant difference to the time it takes to create of
maintain the index.
JS
Taka wrote:
Ah, maybe I wasn't quite clear enough.
What I
Ah, maybe I wasn't quite clear enough.
What I meant was, is there any performance difference between:
CREATE INDEX ON my_table ( a , b , c )
and
CREATE INDEX ON my_table ( c , b , a )
I'm guessing not, presumably because the index is using some kind of hashing
but I thought
Taka wrote:
Does it make a difference what order the columns are specified when
creating an index?
Yes. An index on colums (a, b, c, d) can also speed up search on column
a, on a pair of columns (a, b) and on a triple (a, b, c). If you have a
query with a where clause looking like "where
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