Create an index for the hash component of derivation filenames

This is to aid rendering of narinfo files. They're requested with the path
/HASH.narinfo, so to quickly find the relevant derivation, this index can be
used.

1 files changed, 7 insertions, 0 deletions

diff --git a/sqitch/deploy/derivations_hash_index.sql b/sqitch/deploy/derivations_hash_index.sql
new file mode 100644
index 0000000..869ff0a
--- /dev/null
+++ b/sqitch/deploy/derivations_hash_index.sql
@@ -0,0 +1,7 @@
+-- Deploy guix-data-service:derivations_hash_index to pg
+
+BEGIN;
+
+CREATE INDEX derivations_hash ON derivations (substring(file_name from 12 for 32));
+
+COMMIT;