diff --git a/src/Command/Select.php b/src/Command/Select.php
index de1353b7..4687d484 100644
--- a/src/Command/Select.php
+++ b/src/Command/Select.php
@@ -304,6 +304,20 @@ public function rightJoin(string $table, string $alias, $specification): self
         return $this;
     }
 
+    /**
+     * @see SqlSelect::fullJoin()
+     *
+     * @param string $table The joined table name
+     * @param string $alias The joined table alias
+     * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
+     * @return $this Fluent interface
+     */
+    public function fullJoin(string $table, string $alias, $specification = null): self
+    {
+        $this->sqlStatement->fullJoin($table, $alias, $specification);
+        return $this;
+    }
+
     /**
      * @see SqlSelect::naturalJoin()
      *
@@ -318,6 +332,20 @@ public function naturalJoin(string $table, string $alias, $specification = null)
         return $this;
     }
 
+    /**
+     * @see SqlSelect::naturalInnerJoin()
+     *
+     * @param string $table The joined table name
+     * @param string $alias The joined table alias
+     * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
+     * @return $this Fluent interface
+     */
+    public function naturalInnerJoin(string $table, string $alias, $specification = null): self
+    {
+        $this->sqlStatement->naturalInnerJoin($table, $alias, $specification);
+        return $this;
+    }
+
     /**
      * @see SqlSelect::naturalLeftJoin()
      *
@@ -346,6 +374,20 @@ public function naturalRightJoin(string $table, string $alias, $specification =
         return $this;
     }
 
+    /**
+     * @see SqlSelect::naturalFullJoin()
+     *
+     * @param string $table The joined table name
+     * @param string $alias The joined table alias
+     * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
+     * @return $this Fluent interface
+     */
+    public function naturalFullJoin(string $table, string $alias, $specification = null): self
+    {
+        $this->sqlStatement->naturalFullJoin($table, $alias, $specification);
+        return $this;
+    }
+
     /**
      * @see SqlSelect::crossJoin()
      *
@@ -361,16 +403,16 @@ public function crossJoin(string $table, string $alias, $specification = null):
     }
 
     /**
-     * @see SqlSelect::straightJoin()
+     * @see SqlSelect::unionJoin()
      *
      * @param string $table The joined table name
      * @param string $alias The joined table alias
      * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
      * @return $this Fluent interface
      */
-    public function straightJoin(string $table, string $alias, $specification = null): self
+    public function unionJoin(string $table, string $alias, $specification = null): self
     {
-        $this->sqlStatement->straightJoin($table, $alias, $specification);
+        $this->sqlStatement->unionJoin($table, $alias, $specification);
         return $this;
     }
 
diff --git a/src/Sql.php b/src/Sql.php
index ec7ce697..58318dbe 100644
--- a/src/Sql.php
+++ b/src/Sql.php
@@ -91,26 +91,32 @@ class Sql
      * Join clause types
      */
     public const JOIN_AUTO          = '';
-    public const JOIN_INNER         = 'INNER';
     public const JOIN_CROSS         = 'CROSS';
+    public const JOIN_UNION         = 'UNION';
+    public const JOIN_INNER         = 'INNER';
     public const JOIN_LEFT          = 'LEFT';
     public const JOIN_RIGHT         = 'RIGHT';
-    public const JOIN_STRAIGHT      = 'STRAIGHT';
+    public const JOIN_FULL          = 'FULL';
     public const JOIN_NATURAL       = 'NATURAL';
+    public const JOIN_NATURAL_INNER = 'NATURAL INNER';
     public const JOIN_NATURAL_LEFT  = 'NATURAL LEFT';
     public const JOIN_NATURAL_RIGHT = 'NATURAL RIGHT';
+    public const JOIN_NATURAL_FULL  = 'NATURAL_FULL';
     public const USING              = 'USING';
 
     public const JOIN_TYPES = [
         self::JOIN_AUTO          => self::JOIN_AUTO,
-        self::JOIN_INNER         => self::JOIN_INNER,
         self::JOIN_CROSS         => self::JOIN_CROSS,
+        self::JOIN_UNION         => self::JOIN_UNION,
+        self::JOIN_INNER         => self::JOIN_INNER,
         self::JOIN_LEFT          => self::JOIN_LEFT,
         self::JOIN_RIGHT         => self::JOIN_RIGHT,
-        self::JOIN_STRAIGHT      => self::JOIN_STRAIGHT,
+        self::JOIN_FULL          => self::JOIN_FULL,
         self::JOIN_NATURAL       => self::JOIN_NATURAL,
+        self::JOIN_NATURAL_INNER => self::JOIN_NATURAL_INNER,
         self::JOIN_NATURAL_LEFT  => self::JOIN_NATURAL_LEFT,
         self::JOIN_NATURAL_RIGHT => self::JOIN_NATURAL_RIGHT,
+        self::JOIN_NATURAL_FULL  => self::JOIN_NATURAL_FULL,
     ];
 
     /*
diff --git a/src/Sql/Statement/Select.php b/src/Sql/Statement/Select.php
index d98f6059..2508f8b5 100644
--- a/src/Sql/Statement/Select.php
+++ b/src/Sql/Statement/Select.php
@@ -631,7 +631,7 @@ public function innerJoin(string $table, string $alias, $specification = null):
     }
 
     /**
-     * Add a LEFT JOIN clause
+     * Add a LEFT [OUTER] JOIN clause
      *
      * @param string $table The joined table name
      * @param string $alias The joined table alias
@@ -646,7 +646,7 @@ public function leftJoin(string $table, string $alias, $specification = null): s
     }
 
     /**
-     * Add a RIGHT JOIN clause
+     * Add a RIGHT [OUTER] JOIN clause
      *
      * @param string $table The joined table name
      * @param string $alias The joined table alias
@@ -660,6 +660,21 @@ public function rightJoin(string $table, string $alias, $specification = null):
         );
     }
 
+    /**
+     * Add a FULL [OUTER] JOIN clause
+     *
+     * @param string $table The joined table name
+     * @param string $alias The joined table alias
+     * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
+     * @return $this Fluent interface
+     */
+    public function fullJoin(string $table, string $alias, $specification = null): self
+    {
+        return $this->addJoin(
+            new Join(Sql::JOIN_FULL, $table, $alias, $specification)
+        );
+    }
+
     /**
      * Add a NATURAL JOIN clause
      *
@@ -676,7 +691,22 @@ public function naturalJoin(string $table, string $alias, $specification = null)
     }
 
     /**
-     * Add a NATURAL LEFT JOIN clause
+     * Add a NATURAL INNER JOIN clause
+     *
+     * @param string $table The joined table name
+     * @param string $alias The joined table alias
+     * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
+     * @return $this Fluent interface
+     */
+    public function naturalInnerJoin(string $table, string $alias, $specification = null): self
+    {
+        return $this->addJoin(
+            new Join(Sql::JOIN_NATURAL_INNER, $table, $alias, $specification)
+        );
+    }
+
+    /**
+     * Add a NATURAL LEFT  [OUTER]JOIN clause
      *
      * @param string $table The joined table name
      * @param string $alias The joined table alias
@@ -691,7 +721,7 @@ public function naturalLeftJoin(string $table, string $alias, $specification = n
     }
 
     /**
-     * Add a NATURAL RIGHT JOIN clause
+     * Add a NATURAL RIGHT [OUTER] JOIN clause
      *
      * @param string $table The joined table name
      * @param string $alias The joined table alias
@@ -705,6 +735,21 @@ public function naturalRightJoin(string $table, string $alias, $specification =
         );
     }
 
+    /**
+     * Add a NATURAL FULL [OUTER] JOIN clause
+     *
+     * @param string $table The joined table name
+     * @param string $alias The joined table alias
+     * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
+     * @return $this Fluent interface
+     */
+    public function naturalFullJoin(string $table, string $alias, $specification = null): self
+    {
+        return $this->addJoin(
+            new Join(Sql::JOIN_NATURAL_FULL, $table, $alias, $specification)
+        );
+    }
+
     /**
      * Add a CROSS JOIN clause
      *
@@ -721,17 +766,17 @@ public function crossJoin(string $table, string $alias, $specification = null):
     }
 
     /**
-     * Add a STRAIGHT JOIN clause
+     * Add a UNION JOIN clause
      *
      * @param string $table The joined table name
      * @param string $alias The joined table alias
      * @param On|Predicate|Predicate\Set|array|string|Literal|Identifier|null $specification
      * @return $this Fluent interface
      */
-    public function straightJoin(string $table, string $alias, $specification = null): self
+    public function unionJoin(string $table, string $alias, $specification = null): self
     {
         return $this->addJoin(
-            new Join(Sql::JOIN_STRAIGHT, $table, $alias, $specification)
+            new Join(Sql::JOIN_UNION, $table, $alias, $specification)
         );
     }
 
diff --git a/test/Command/SelectTest.php b/test/Command/SelectTest.php
index 1b6c9d9a..9b506ae7 100644
--- a/test/Command/SelectTest.php
+++ b/test/Command/SelectTest.php
@@ -385,11 +385,14 @@ public function provideJoinOptions(): array
             ['crossJoin', Sql::JOIN_CROSS],
             ['innerJoin', Sql::JOIN_INNER],
             ['leftJoin', Sql::JOIN_LEFT],
+            ['rightJoin', Sql::JOIN_RIGHT],
+            ['fullJoin', Sql::JOIN_FULL],
             ['naturalJoin', Sql::JOIN_NATURAL],
+            ['naturalInnerJoin', Sql::JOIN_NATURAL_INNER],
             ['naturalLeftJoin', Sql::JOIN_NATURAL_LEFT],
             ['naturalRightJoin', Sql::JOIN_NATURAL_RIGHT],
-            ['rightJoin', Sql::JOIN_RIGHT],
-            ['straightjoin', Sql::JOIN_STRAIGHT],
+            ['naturalfullJoin', Sql::JOIN_NATURAL_FULL],
+            ['unionjoin', Sql::JOIN_UNION],
         ];
     }