refactor: Optimize getUserIdMappingWithEitherSuperTokensUserIdOrExternalUserId query (#243)

Co-authored-by: Sattvik Chakravarthy <sattvik@supertokens.com>

Author: mavwolverine

CHANGELOG.md

@@ -10,6 +10,7 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 ## [7.3.0] 
 
 - Adds tables and queries for Bulk Import
+- Optimize getUserIdMappingWithEitherSuperTokensUserIdOrExternalUserId query
 
 ### Migration
 
@@ -34,6 +35,7 @@ CREATE INDEX IF NOT EXISTS bulk_import_users_pagination_index1 ON bulk_import_us
  
 CREATE INDEX IF NOT EXISTS bulk_import_users_pagination_index2 ON bulk_import_users (app_id, created_at DESC, id DESC);
 ```
+
 ## [7.2.0] - 2024-10-03
 
 - Compatible with plugin interface version 6.3

src/main/java/io/supertokens/storage/postgresql/queries/UserIdMappingQueries.java

@@ -139,12 +139,16 @@ public static UserIdMapping[] getUserIdMappingWithEitherSuperTokensUserIdOrExter
                                                                                               String userId)
             throws SQLException, StorageQueryException {
         String QUERY = "SELECT * FROM " + Config.getConfig(start).getUserIdMappingTable()
-                + " WHERE app_id = ? AND (supertokens_user_id = ? OR external_user_id = ?)";
+                + " WHERE app_id = ? AND supertokens_user_id = ?"
+                + " UNION ALL "
+                + "SELECT * FROM " + Config.getConfig(start).getUserIdMappingTable()
+                + " WHERE app_id = ? AND external_user_id = ?";
 
         return execute(start, QUERY, pst -> {
             pst.setString(1, appIdentifier.getAppId());
             pst.setString(2, userId);
-            pst.setString(3, userId);
+            pst.setString(3, appIdentifier.getAppId());
+            pst.setString(4, userId);
         }, result -> {
             ArrayList<UserIdMapping> userIdMappingArray = new ArrayList<>();
             while (result.next()) {
@@ -375,12 +379,16 @@ public static UserIdMapping[] getUserIdMappingWithEitherSuperTokensUserIdOrExter
                                                                                                           String userId)
             throws SQLException, StorageQueryException {
         String QUERY = "SELECT * FROM " + Config.getConfig(start).getUserIdMappingTable()
-                + " WHERE app_id = ? AND (supertokens_user_id = ? OR external_user_id = ?)";
+                + " WHERE app_id = ? AND supertokens_user_id = ?"
+                + " UNION ALL "
+                + "SELECT * FROM " + Config.getConfig(start).getUserIdMappingTable()
+                + " WHERE app_id = ? AND external_user_id = ?";
 
         return execute(sqlCon, QUERY, pst -> {
             pst.setString(1, appIdentifier.getAppId());
             pst.setString(2, userId);
-            pst.setString(3, userId);
+            pst.setString(3, appIdentifier.getAppId());
+            pst.setString(4, userId);
         }, result -> {
             ArrayList<UserIdMapping> userIdMappingArray = new ArrayList<>();
             while (result.next()) {