Query to find B-tree indexes on array columns (#35)

* Query to find B-tree indexes on array columns

* Bump super-linter from slim-v5 to slim-v6

* Rewrite query

* Minor improvements

---------

Co-authored-by: Vadim Khizhin <khizhinvadim@gmail.com>

.github/linters/.sqlfluff

@@ -1,6 +1,6 @@
 [sqlfluff]
 dialect = postgres
-exclude_rules = LT01, LT02, LT03, LT08, AM03, AM05, AL01, AL05, ST06
+exclude_rules = LT01, LT02, LT03, LT08, AM03, AM05, AL01, AL05, ST06, ST09
 warnings = AM06, ST05
 max_line_length = 180
 templater = raw

.github/workflows/linter.yml

@@ -18,7 +18,7 @@ jobs:
           fetch-depth: 0
 
       - name: Lint Code Base
-        uses: github/super-linter/slim@v5
+        uses: github/super-linter/slim@v6
         env:
           VALIDATE_ALL_CODEBASE: false
           VALIDATE_SQLFLUFF: true

README.md

@@ -44,8 +44,7 @@ To run super-linter locally
 docker run \
   -e RUN_LOCAL=true \
   -e USE_FIND_ALGORITHM=true \
-  -e VALIDATE_ALL_CODEBASE=false \
   -e VALIDATE_SQLFLUFF=true \
   -v $(pwd):/tmp/lint \
-  github/super-linter:slim-v5
+  ghcr.io/super-linter/super-linter:slim-v6
 ```

sql/bloated_indexes.sql

@@ -57,7 +57,7 @@ named_indexes_attributes as (
         ic.inner_index_name,
         ic.attpos,
         ic.indkey,
-        ic.indkey[ic.attpos],
+        ic.indkey[ic.attpos] as indattpos,
         ic.reltuples,
         ic.relpages,
         ic.index_oid,

sql/btree_indexes_on_array_columns.sql

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2019-2024. Ivan Vakhrushev and others.
+ * https://github.com/mfvanek/pg-index-health-sql
+ *
+ * Licensed under the Apache License 2.0
+ */
+
+-- Finds B-tree indexes on array columns
+--
+-- GIN-index should be used instead for such columns
+-- Based on query from https://habr.com/ru/articles/800121/
+select
+    i.indrelid::regclass as table_name,  -- Name of the table
+    i.indexrelid::regclass as index_name, -- Name of the index
+    col.attname as column_name, -- Column name
+    col.attnotnull as column_not_null -- Column not null
+from pg_catalog.pg_index as i
+    inner join pg_catalog.pg_class as ic on i.indexrelid = ic.oid
+    inner join pg_catalog.pg_namespace as nsp on nsp.oid = ic.relnamespace
+    inner join pg_catalog.pg_am as a on ic.relam = a.oid and a.amname = 'btree'
+    inner join pg_catalog.pg_attribute as col on i.indrelid = col.attrelid and col.attnum = any((string_to_array(i.indkey::text, ' ')::int2[])[:i.indnkeyatts])
+    inner join pg_catalog.pg_type as typ on typ.oid = col.atttypid
+where
+	nsp.nspname = :schema_name_param::text and
+	typ.typcategory = 'A' -- A stands for Array type. See - https://www.postgresql.org/docs/current/catalog-pg-type.html#CATALOG-TYPCATEGORY-TABLE
+order by ic.oid::regclass::text, i.indexrelid::regclass::text;