add script to migrate postgres versions

docker-resources/migrate-postgresql-version.sh

@@ -0,0 +1,40 @@
+#!/bin/bash
+
+# USAGE:
+# migrate-postgresql-version.sh <data_directory> <old_version> <new_version>
+
+if [ "$#" -ne 3 ]; then
+    echo "USAGE: migrate-postgresql-version.sh <data_directory> <old_version> <new_version>"
+    echo "Example: migrate-postgresql-version.sh pgdata 14 16"
+    exit 1
+fi
+
+data_directory=$1
+old_version=$2
+new_version=$3
+
+# Start a PostgreSQL 14 container
+docker run --rm -d --name pg14 -v $(pwd)/$data_directory:/var/lib/postgresql/data postgres:$old_version
+
+# Dump the db from the old container
+docker exec pg14 pg_dumpall -U postgres > dump.sql
+
+# Stop the old container
+docker stop pg14
+
+# move the data directory to a new location so we can overwrite it
+mv $data_directory $data_directory.bak
+
+# Start a PostgreSQL 16 container
+docker run --rm -d --name pg16 -v $(pwd)/$data_directory:/var/lib/postgresql/data postgres:$new_version
+
+# Load the db into the new container
+docker exec -i pg16 psql -U postgres < dump.sql
+
+# Stop the new container
+docker stop pg16
+
+# Remove the dump file
+rm dump.sql
+
+echo "Migration complete! You can delete your old data directory by running 'rm -rf $data_directory.bak'"