Change migration batching approach to avoid problematic syntax on MySQL (#2506)

Users have reported compatibility issues with the recent batched update
approach used in several migrations, including #2496. MySQL 8.3 does not
support LIMIT clauses on multi-table update statements.

This PR changes the batching approach used for the two migrations
affected by these issues to avoid the problematic syntax.

Author: williamjallen

database/migrations/2024_08_24_160326_label2test_relationship_refactor.php

@@ -18,10 +18,10 @@ public function up(): void
                 ->nullable();
         });
 
-        if (config('database.default') === 'pgsql') {
-            $count = (int) DB::select('SELECT count(1) AS c FROM build')[0]->c;
+        $count = (int) DB::select('SELECT count(1) AS c FROM build')[0]->c;
 
-            // Execute at most 10k batches of buildwise updates
+        // Execute at most 10k batches of buildwise updates
+        if (config('database.default') === 'pgsql') {
             for ($i = 0; $i < ceil($count / 10000); $i++) {
                 DB::update('
                     UPDATE label2test
@@ -35,18 +35,16 @@ public function up(): void
                 ', [$i]);
             }
         } else {
-            // MySQL is a bit more finicky about large transactions, so update in batches of 100
-            $rows_changed = 1;
-            while ($rows_changed > 0) {
-                $rows_changed = DB::update('
+            for ($i = 0; $i < ceil($count / 10000); $i++) {
+                DB::update('
                     UPDATE label2test, build2test
                     SET label2test.testid = build2test.id
                     WHERE
                         build2test.buildid = label2test.buildid
                         AND build2test.outputid = label2test.outputid
                         AND label2test.testid IS NULL
-                    LIMIT 100
-                ');
+                        AND build2test.buildid % ? = 0
+                ', [$i]);
             }
         }
 

database/migrations/2024_10_13_160937_buildinformation_to_build_table.php

@@ -34,30 +34,18 @@ public function up(): void
                 WHERE build.id = buildinformation.buildid
             ');
         } else {
-            // MySQL is a bit more finicky about large transactions, so update in batches of 100
-            $rows_changed = 1;
-            while ($rows_changed > 0) {
-                $rows_changed = DB::update('
-                    UPDATE build, buildinformation
-                    SET
-                        build.osname = buildinformation.osname,
-                        build.osplatform = buildinformation.osplatform,
-                        build.osrelease = buildinformation.osrelease,
-                        build.osversion = buildinformation.osversion,
-                        build.compilername = buildinformation.compilername,
-                        build.compilerversion = buildinformation.compilerversion
-                    WHERE build.id = buildinformation.buildid
-                    LIMIT 100
-                ');
-
-                // Delete the rows we just moved over
-                DB::delete('
-                    DELETE FROM buildinformation
-                    WHERE buildid IN (
-                        SELECT id FROM build
-                    )
-                ');
-            }
+            DB::update('
+                UPDATE build, buildinformation
+                SET
+                    build.osname = buildinformation.osname,
+                    build.osplatform = buildinformation.osplatform,
+                    build.osrelease = buildinformation.osrelease,
+                    build.osversion = buildinformation.osversion,
+                    build.compilername = buildinformation.compilername,
+                    build.compilerversion = buildinformation.compilerversion
+                WHERE
+                    build.id = buildinformation.buildid
+            ');
         }
 
         Schema::dropIfExists('buildinformation');