simplify sql statement

Author: kvch

pkg/stream/config.go

@@ -168,7 +168,6 @@ func (c *Config) validateTableSelections() error {
 	return nil
 }
 
-
 func (c *Config) SourcePostgresURL() string {
 	if c.Listener.Postgres != nil {
 		return c.Listener.Postgres.URL

pkg/stream/preflight/replica_identity.go

@@ -28,24 +28,21 @@ SELECT
   n.nspname,
   c.relname,
   c.relreplident::text,
-  EXISTS (
-    SELECT 1 FROM pg_index i
-    WHERE i.indrelid = c.oid AND i.indisprimary
-  ) AS has_pk,
-  COALESCE(
-    (
-      SELECT i.indisvalid AND i.indisunique AND i.indpred IS NULL
-             AND NOT EXISTS (
-               SELECT 1 FROM unnest(i.indkey) k
-               JOIN pg_attribute a ON a.attrelid = c.oid AND a.attnum = k
-               WHERE NOT a.attnotnull
-             )
-      FROM pg_index i WHERE i.indrelid = c.oid AND i.indisreplident
-    ),
-    false
+  pk.indrelid IS NOT NULL AS has_pk,
+  ri.indrelid IS NOT NULL AND NOT EXISTS (
+    SELECT 1 FROM pg_attribute a
+    WHERE a.attrelid = c.oid
+      AND a.attnum = ANY (ri.indkey::int[])
+      AND NOT a.attnotnull
   ) AS replident_index_ok
 FROM pg_class c
 JOIN pg_namespace n ON n.oid = c.relnamespace
+LEFT JOIN pg_index pk ON pk.indrelid = c.oid AND pk.indisprimary
+LEFT JOIN pg_index ri ON ri.indrelid = c.oid
+                     AND ri.indisreplident
+                     AND ri.indisvalid
+                     AND ri.indisunique
+                     AND ri.indpred IS NULL
 WHERE c.relkind = 'r'
   AND n.nspname NOT IN ('pg_catalog', 'information_schema', 'pgstream')
 ORDER BY n.nspname, c.relname