WIP Prepare postgres for migration by replication

site-cookbooks/kosmos_postgresql/files/fix_sequences_in_all_databases.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+set -e
+
+echo "== Fixing sequences across all databases =="
+
+for db in $(psql -Atqc "SELECT datname FROM pg_database WHERE datallowconn AND datname NOT IN ('template1')"); do
+  echo "---- DB: $db ----"
+
+  # Generate fix statements
+  SQL=$(psql -d "$db" -Atqc "
+    SELECT
+      'SELECT setval(' ||
+      quote_literal(pg_get_serial_sequence(quote_ident(n.nspname)||'.'||quote_ident(c.relname), a.attname)) ||
+      ', COALESCE(MAX(' || quote_ident(a.attname) || '), 0) + 1, false) FROM ' ||
+      quote_ident(n.nspname)||'.'||quote_ident(c.relname) || ';'
+    FROM pg_class c
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    JOIN pg_attribute a ON a.attrelid = c.oid
+    WHERE c.relkind = 'r'
+      AND a.attnum > 0
+      AND NOT a.attisdropped
+      AND pg_get_serial_sequence(quote_ident(n.nspname)||'.'||quote_ident(c.relname), a.attname) IS NOT NULL;
+  ")
+
+  if [ -z "$SQL" ]; then
+    echo "No sequences found in $db"
+    continue
+  fi
+
+  echo "Fixing sequences in $db..."
+
+  # Execute generated statements
+  echo "$SQL" | psql -d "$db"
+
+done
+
+echo "== Done fixing sequences =="
+