From ddd547bc4090e5a17a67350fcc409ff5c1d1ba18 Mon Sep 17 00:00:00 2001
From: Andrew Atkinson <andyatkinson@gmail.com>
Date: Mon, 9 Dec 2024 15:13:25 -0600
Subject: [PATCH 1/2] Index analysis queries

---
 index_analysis_content_indexes.sql | 90 ++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 index_analysis_content_indexes.sql

diff --git a/index_analysis_content_indexes.sql b/index_analysis_content_indexes.sql
new file mode 100644
index 0000000..75d8d85
--- /dev/null
+++ b/index_analysis_content_indexes.sql
@@ -0,0 +1,90 @@
+-- Indexes in 'public' schema that are
+-- "content" indexes, i.e. they aren't system indexes
+-- for primary keys, unique constraints
+SELECT
+    n.nspname AS schema_name,
+    c.relname AS index_name,
+    t.relname AS table_name,
+    pg_index.indisunique AS is_unique,
+    pg_index.indisprimary AS is_primary
+FROM
+    pg_index
+    JOIN pg_class c ON c.oid = pg_index.indexrelid
+    JOIN pg_class t ON t.oid = pg_index.indrelid
+    JOIN pg_namespace n ON n.oid = t.relnamespace
+WHERE
+    n.nspname = 'public'
+    AND NOT pg_index.indisunique
+    AND NOT pg_index.indisprimary;
+
+
+-- Join to pg_constraint
+-- to exclude foreign key constraint indexes
+SELECT
+    n.nspname AS schema_name,
+    c.relname AS index_name,
+    t.relname AS table_name
+FROM
+    pg_index
+JOIN
+    pg_class c ON c.oid = pg_index.indexrelid
+JOIN
+    pg_class t ON t.oid = pg_index.indrelid
+JOIN
+    pg_namespace n ON n.oid = t.relnamespace
+LEFT JOIN
+    pg_constraint con ON con.conindid = pg_index.indexrelid
+WHERE
+    n.nspname = 'public'
+-- https://mohyusufz.medium.com/how-to-check-for-indexes-on-foreign-key-columns-in-postgresql-450159772f8e#:~:text=Checking%20for%20Indexes%3A,%2C%20it%20displays%20%22Unindexed.%22
+    AND NOT pg_index.indisprimary
+    AND con.contype IS NULL; -- Excludes indexes associated with constraints
+
+
+-- Find foreign key indexes
+-- Credit: https://mohyusufz.medium.com/how-to-check-for-indexes-on-foreign-key-columns-in-postgresql-450159772f8e
+WITH fk_constraints AS (
+    SELECT
+        c.conrelid::regclass AS table,
+        c.conname AS constraint,
+        string_agg(a.attname, ',' ORDER BY x.n) AS columns,
+        pg_catalog.pg_size_pretty(pg_catalog.pg_relation_size(c.conrelid)) AS size,
+        c.confrelid::regclass AS referenced_table,
+        c.conkey AS conkey,
+        c.conrelid AS conrelid
+    FROM
+        pg_catalog.pg_constraint c
+        /* Enumerated key column numbers per foreign key */
+        CROSS JOIN LATERAL unnest(c.conkey)
+        WITH ORDINALITY AS x (attnum, n)
+        /* Join to get the column names */
+        JOIN pg_catalog.pg_attribute a ON a.attnum = x.attnum
+            AND a.attrelid = c.conrelid
+    WHERE
+        /* Ensure the constraint is a foreign key */
+        c.contype = 'f'
+    GROUP BY
+        c.conrelid,
+        c.conname,
+        c.confrelid,
+        c.conkey
+)
+SELECT
+    fk.table,
+    fk.constraint,
+    fk.columns,
+    fk.size,
+    fk.referenced_table,
+    /* Retrieve the index name or mark as Unindexed */
+    COALESCE((
+        SELECT
+            i.indexrelid::regclass::text
+        FROM pg_catalog.pg_index i
+        WHERE
+            i.indrelid = fk.conrelid
+            AND i.indpred IS NULL
+            AND (i.indkey::smallint[])[0:cardinality(fk.conkey) - 1] OPERATOR (pg_catalog. @>) fk.conkey LIMIT 1), 'Unindexed') AS index_name
+FROM
+    fk_constraints fk
+ORDER BY
+    pg_catalog.pg_relation_size(fk.conrelid) DESC;

From 4a928ec7a23ba5d45ee3982b9fc19fb02afd34e4 Mon Sep 17 00:00:00 2001
From: Andrew Atkinson <andyatkinson@gmail.com>
Date: Mon, 9 Dec 2024 15:15:04 -0600
Subject: [PATCH 2/2] Remove stray line

---
 index_analysis_content_indexes.sql | 1 -
 1 file changed, 1 deletion(-)

diff --git a/index_analysis_content_indexes.sql b/index_analysis_content_indexes.sql
index 75d8d85..32cd65a 100644
--- a/index_analysis_content_indexes.sql
+++ b/index_analysis_content_indexes.sql
@@ -36,7 +36,6 @@ LEFT JOIN
     pg_constraint con ON con.conindid = pg_index.indexrelid
 WHERE
     n.nspname = 'public'
--- https://mohyusufz.medium.com/how-to-check-for-indexes-on-foreign-key-columns-in-postgresql-450159772f8e#:~:text=Checking%20for%20Indexes%3A,%2C%20it%20displays%20%22Unindexed.%22
     AND NOT pg_index.indisprimary
     AND con.contype IS NULL; -- Excludes indexes associated with constraints