check_connection fails

[Yogurt4]

WP Version: 6.8.3
PG4WP Version: 3.4.1

Error:

Fatal error: Uncaught Exception: Invalid or unsupported SQL statement. in /var/www/html/wp-content/pg4wp/driver_pgsql_rewrite.php:26
Stack trace:
#0 /var/www/html/wp-content/pg4wp/driver_pgsql_rewrite.php(40): createSQLRewriter('DO 1')
#1 /var/www/html/wp-content/pg4wp/driver_pgsql.php(523): pg4wp_rewrite('DO 1')
#2 /var/www/html/wp-content/pg4wp/core.php(34) : eval()'d code(2124): wpsqli_query(Object(PgSql\Connection), 'DO 1')
#3 /var/www/html/wp-content/plugins/health-endpoint/health-endpoint.php(60): wpdb2->check_connection(false)
#4 /var/www/html/wp-includes/class-wp-hook.php(324): health_check_request(Object(WP))
#5 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)
#6 /var/www/html/wp-includes/plugin.php(565): WP_Hook->do_action(Array)
#7 /var/www/html/wp-includes/class-wp.php(418): do_action_ref_array('parse_request', Array)
#8 /var/www/html/wp-includes/class-wp.php(818): WP->parse_request('')
#9 /var/www/html/wp-includes/functions.php(1342): WP->main('')
#10 /var/www/html/wp-blog-header.php(16): wp()
#11 /var/www/html/index.php(17): require('/var/www/html/w...')
#12 {main}
  thrown in /var/www/html/wp-content/pg4wp/driver_pgsql_rewrite.php on line 26

RAW SQL

DO 1

Expected Rewritten SQL

SELECT 1

or

DO $$ BEGIN NULL; END $$

Actual Rewritten SQL

DO 1

This statement is created by the WP core class-wpdb.php, in function check_connection().

As a quick fix, I've added

   if ($sql === 'DO 1')
       return 'SELECT 1;';

to the start of pg4wp_rewrite().