Fix database command warnings

app/src/Lib/Util/SchemaManager.php

@@ -327,14 +327,16 @@ protected function processSchema(
     }
 
     // This is the SQL that represents the desired state of the database
+    // XXX This never used
     $toSql = $schema->toSql($this->conn->getDatabasePlatform());
 
     // SchemaManager provides info about the database
     $sm = $this->conn->createSchemaManager();
 
-    // The is the current database representation
-    $curSchema = $sm->createSchema();
-
+    // This is the current database representation
+    $curSchema = $sm->introspectSchema();
+
+    // XXX This is never used
     $fromSql = $curSchema->toSql($this->conn->getDatabasePlatform());
 
     try {
@@ -359,12 +361,43 @@ protected function processSchema(
           // Remove the DROP SEQUENCE statements in $fromSql because they're Postgres automagic
           // being misinterpreted. (Note toSaveSql might mask this now.)
           // XXX Maybe debug and file a PR to not emit DROP SEQUENCE on PG for autoincrementesque fields?
-          if($this->io) $io->out("Skipping sequence drop");
-        } else {
+          if($this->io) $this->io->out("Skipping sequence drop");
+          continue;
+        }
+
+        // PostgreSQL: translate DROP INDEX for names that are actually unique constraints
+        if($this->conn->driver == 'Cake\Database\Driver\Postgres'
+           && preg_match('/^DROP INDEX\s+"?([a-zA-Z0-9_\.]+)"?/i', $sql, $m)) {
+          $idxOrConstraint = $m[1];
+
+          // Resolve if this name is a constraint and on which table
+          $qualifiedTable = $this->resolvePgConstraintTable($idxOrConstraint);
+
+          if($qualifiedTable !== null) {
+            // We will skip this index if it's bound to a constraint
+            if($this->io) $this->io->out('Skipping index drop since it is bound to a constraint');
+            continue;
+          }
+        }
+
+        // PostgreSQL: make index renames idempotent and tolerant using IF EXISTS
+        if($this->conn->driver == 'Cake\Database\Driver\Postgres'
+           && preg_match('/^ALTER INDEX\s+([^\s]+)\s+RENAME\s+TO\s+([^\s]+)$/i', trim($sql), $m)) {
+          $oldName = $m[1];
+          $newName = $m[2];
+
+          // Use IF EXISTS to avoid error if the old index name doesn't exist in this environment
+          $translated = 'ALTER INDEX IF EXISTS ' . $oldName . ' RENAME TO ' . $newName;
+          if($this->io) $this->io->out($translated . '  -- added IF EXISTS for PostgreSQL resilience');
           if(!$diffOnly) {
-            $stmt = $this->conn->executeQuery($sql);
-            // $stmt just returns the query string so we don't bother examining it
+            $this->conn->executeQuery($translated);
           }
+          continue;
+        }
+
+        if(!$diffOnly) {
+          $stmt = $this->conn->executeQuery($sql);
+          // $stmt just returns the query string so we don't bother examining it
         }
       }
 
@@ -380,4 +413,42 @@ protected function processSchema(
     // but so far we don't have an example indicating it's needed.
   }
 
-}
+  /**
+   * Resolve a PostgreSQL constraint's owning table (schema-qualified) by constraint name.
+   * Returns null if the given name is not found as a constraint.
+   *
+   * @param string $constraintName
+   * @return ?string Schema-qualified table name or null if constraint not found
+   * @since  COmanage Registry v5.2.0
+   */
+
+  protected function resolvePgConstraintTable(string $constraintName): ?string {
+    if($this->conn->driver !== 'Cake\\Database\\Driver\\Postgres') {
+      return null;
+    }
+
+    // Query pg catalogs to find the table for this constraint name
+    // We return schema-qualified name: schema.table
+    $sql = <<<CATALOG
+      SELECT n.nspname AS schema, c.relname AS table
+      FROM pg_constraint co
+      JOIN pg_class c ON c.oid = co.conrelid
+      JOIN pg_namespace n ON n.oid = c.relnamespace
+      WHERE co.conname = :name
+      LIMIT 1
+CATALOG;
+
+    try {
+      $stmt = $this->conn->executeQuery($sql, ['name' => $constraintName]);
+      $row = $stmt->fetchAssociative();
+      if(!$row || empty($row['schema']) || empty($row['table'])) {
+        return null;
+      }
+      // Quote/qualify as schema.table (matching how other statements look)
+      return $row['schema'] . '.' . $row['table'];
+    } catch(\Throwable $e) {
+      // On any error, fail open by returning null so caller uses original SQL
+      return null;
+    }
+  }
+}