Execute Query without ->from() (#238)

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Enh #248: Change property `Schema::$typeMap` to constant `Schema::TYPE_MAP` (@Tigrov)
 - Bug #250: Fix `Command::insertWithReturningPks()` method for table without primary keys (@Tigrov)
 - Enh #251: Allow to use `DMLQueryBuilderInterface::batchInsert()` method with empty columns (@Tigrov)
+- Bug #238: Fix execution `Query` without table(s) to select from (@Tigrov)
 
 ## 1.2.0 November 12, 2023
 

src/DQLQueryBuilder.php

@@ -61,6 +61,15 @@ public function selectExists(string $rawSql): string
         return 'SELECT CASE WHEN EXISTS(' . $rawSql . ') THEN 1 ELSE 0 END FROM DUAL';
     }
 
+    public function buildFrom(array|null $tables, array &$params): string
+    {
+        if (empty($tables)) {
+            return 'FROM DUAL';
+        }
+
+        return parent::buildFrom($tables, $params);
+    }
+
     public function buildWithQueries(array $withs, array &$params): string
     {
         /** @psalm-var array{query:string|Query, alias:ExpressionInterface|string, recursive:bool}[] $withs */

tests/QueryBuilderTest.php

@@ -230,7 +230,7 @@ public function testBuildWithLimit(): void
 
         $this->assertSame(
             <<<SQL
-            WITH USER_SQL AS (SELECT *), PAGINATION AS (SELECT USER_SQL.*, rownum as rowNumId FROM USER_SQL)
+            WITH USER_SQL AS (SELECT * FROM DUAL), PAGINATION AS (SELECT USER_SQL.*, rownum as rowNumId FROM USER_SQL)
             SELECT * FROM PAGINATION WHERE rownum <= 10
             SQL,
             $sql,
@@ -257,7 +257,7 @@ public function testBuildWithOffset(): void
 
         $this->assertSame(
             <<<SQL
-            WITH USER_SQL AS (SELECT *), PAGINATION AS (SELECT USER_SQL.*, rownum as rowNumId FROM USER_SQL)
+            WITH USER_SQL AS (SELECT * FROM DUAL), PAGINATION AS (SELECT USER_SQL.*, rownum as rowNumId FROM USER_SQL)
             SELECT * FROM PAGINATION WHERE rowNumId > 10
             SQL,
             $sql,