Add length() perturbation to translate_table_ref AUTO_INCREMENT subquery

testInformationSchemaTablesFilterByAutoIncrement fails on Turso
mid-suite: WHERE on the AUTO_INCREMENT alias of a correlated
subquery in the derived-table SELECT list returns 0 rows. CI probe
of the same shape on a fresh PDO works, so the bug is
state-dependent — likely Turso's optimizer caches the subquery
result across rows after some prior tests run.

The probe also tested adding `AND length(<alias>.table_name) > 0`
to the correlated subquery's WHERE — same result on isolation but
it forces a fresh outer-column reference at each evaluation, which
should defeat any cross-row caching.

Apply that perturbation here. The shape of translate_table_ref's
output is otherwise unchanged, so we hope this avoids the
testReconstructTable pager fragility that the JOIN-form rewrite
triggered.

Author: JanJakes

.github/workflows/phpunit-tests-turso.yml

@@ -1905,6 +1905,66 @@ jobs:
           #     The two temp-table tests stay failing under Turso. No
           #     driver-side workaround found that doesn't break a
           #     currently-passing test.
+
+          # 21. testInformationSchemaTablesFilterByAutoIncrement fails on
+          #     Turso mid-suite because the WHERE filter on the AUTO_INCREMENT
+          #     alias of a correlated subquery in a derived-table SELECT
+          #     list returns 0 rows. CI probe of the exact same query
+          #     shape on a fresh PDO returns the correct rows, so the bug
+          #     is state-dependent.
+          #
+          #     The probe also showed that adding `AND length(<alias>.table_name) > 0`
+          #     to the correlated subquery's WHERE clause works (forces a
+          #     fresh outer-column reference at each evaluation). Apply
+          #     that perturbation here. This change keeps the overall
+          #     translate_table_ref shape identical except for one extra
+          #     redundant predicate in the WHERE — which we hope doesn't
+          #     trigger Turso's testReconstructTable pager fragility the
+          #     way restructuring to a JOIN form did.
+          path = 'src/sqlite/class-wp-pdo-mysql-on-sqlite.php'
+          src = open(path).read()
+          old_corr = (
+              "\t\t\t\t\t$auto_increment_subquery = sprintf(\n"
+              "\t\t\t\t\t\t\"(\n"
+              "\t\t\t\t\t\t\tSELECT COALESCE(s.seq + 1, 1)\n"
+              "\t\t\t\t\t\t\tFROM %s AS c\n"
+              "\t\t\t\t\t\t\t%s\n"
+              "\t\t\t\t\t\t\tWHERE c.extra = 'auto_increment'\n"
+              "\t\t\t\t\t\t\tAND c.table_schema = %s.table_schema\n"
+              "\t\t\t\t\t\t\tAND c.table_name = %s.table_name\n"
+              "\t\t\t\t\t\t)\",\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $columns_table ),\n"
+              "\t\t\t\t\t\t$has_sequence_table\n"
+              "\t\t\t\t\t\t\t? 'LEFT JOIN main.sqlite_sequence AS s ON s.name = c.table_name'\n"
+              "\t\t\t\t\t\t\t: 'LEFT JOIN (SELECT 0 AS seq) AS s',\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $table_name ),\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $table_name )\n"
+              "\t\t\t\t\t);\n"
+          )
+          new_corr = (
+              "\t\t\t\t\t$auto_increment_subquery = sprintf(\n"
+              "\t\t\t\t\t\t\"(\n"
+              "\t\t\t\t\t\t\tSELECT COALESCE(s.seq + 1, 1)\n"
+              "\t\t\t\t\t\t\tFROM %s AS c\n"
+              "\t\t\t\t\t\t\t%s\n"
+              "\t\t\t\t\t\t\tWHERE c.extra = 'auto_increment'\n"
+              "\t\t\t\t\t\t\tAND c.table_schema = %s.table_schema\n"
+              "\t\t\t\t\t\t\tAND c.table_name = %s.table_name\n"
+              "\t\t\t\t\t\t\tAND length(%s.table_name) > 0\n"
+              "\t\t\t\t\t\t)\",\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $columns_table ),\n"
+              "\t\t\t\t\t\t$has_sequence_table\n"
+              "\t\t\t\t\t\t\t? 'LEFT JOIN main.sqlite_sequence AS s ON s.name = c.table_name'\n"
+              "\t\t\t\t\t\t\t: 'LEFT JOIN (SELECT 0 AS seq) AS s',\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $table_name ),\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $table_name ),\n"
+              "\t\t\t\t\t\t$this->quote_sqlite_identifier( $table_name )\n"
+              "\t\t\t\t\t);\n"
+          )
+          assert old_corr in src, 'translate_table_ref AUTO_INCREMENT correlated subquery not found'
+          src = src.replace(old_corr, new_corr, 1)
+          open(path, 'w').write(src)
+          print('patched translate_table_ref AUTO_INCREMENT correlated subquery with length() perturbation')
           PY
 
       - name: Run PHPUnit tests against Turso DB