plpgsql NULL and RETURN STATEMENTS (#18623)

* plpgsql RETURN statements with no expression
* plpgsql NULL statements

src/current/v24.1/create-function.md

@@ -31,7 +31,7 @@ If you grant `EXECUTE` privilege as a default privilege at the database level, n
 Parameter | Description
 ----------|------------
 `routine_create_name` | The name of the function.
-`routine_param` | A comma-separated list of function parameters.
+`routine_param` | A comma-separated list of function parameters, specifying the mode, name, and type.
 `routine_return_type` | The type returned by the function. 
 `routine_body_str` | The body of the function. For allowed contents, see [User-Defined Functions]({% link {{ page.version.version }}/user-defined-functions.md %}#overview).
 

src/current/v24.1/create-procedure.md

@@ -29,8 +29,8 @@ If you grant `EXECUTE` privilege as a default privilege at the database level, n
 |       Parameter       |                                                                   Description                                                                   |
 |-----------------------|-------------------------------------------------------------------------------------------------------------------------------------------------|
 | `routine_create_name` | The name of the procedure.                                                                                                                      |
-| `routine_param`       | A comma-separated list of procedure parameters.                                                                                                                          |
-| `routine_body_str`   | The body of the procedure. For allowed contents, see [Stored Procedures]({% link {{ page.version.version }}/stored-procedures.md %}#structure). |
+| `routine_param`       | A comma-separated list of procedure parameters, specifying the mode, name, and type.                                                            |
+| `routine_body_str`    | The body of the procedure. For allowed contents, see [Stored Procedures]({% link {{ page.version.version }}/stored-procedures.md %}#structure). |
 
 ## Examples
 

src/current/v24.1/plpgsql.md

@@ -40,7 +40,7 @@ At the highest level, a PL/pgSQL block looks like the following:
   END
 ~~~
 
-PL/pgSQL blocks can be nested. An optional label can be placed above each block. Block labels can be targeted by [`EXIT` statements](#exit-and-continue-statements).
+PL/pgSQL blocks can be nested. An optional label can be placed above each block. Block labels can be targeted by [`EXIT` statements](#exit).
 
 ~~~ sql
 [ <<outer_block>> ]
@@ -217,7 +217,6 @@ IF condition THEN
 
 `IF ... THEN ... ELSIF` executes statements if a boolean condition is true. If the condition is false, each `ELSIF` condition is evaluated until one is true. The corresponding `ELSIF` statements are executed. If no `ELSIF` conditions are true, no statements are executed unless an `ELSE` clause is included, in which case the `ELSE` statements are executed.
 
-{% include_cached copy-clipboard.html %}
 ~~~ sql
 IF condition THEN
 	statements;
@@ -230,6 +229,14 @@ IF condition THEN
   END IF;
 ~~~
 
+`IF`, `ELSE`, and `ELSIF` conditions are not required to execute statements. You can exclude any statements or add a placeholder `NULL` statement.
+
+~~~ sql
+IF condition THEN
+	NULL;
+  END IF;
+~~~
+
 For usage examples of conditional statements, see [Examples](#examples).
 
 ### Write loops
@@ -254,7 +261,9 @@ WHILE condition LOOP
 
 For an example, see [Create a stored procedure that uses a `WHILE` loop]({% link {{ page.version.version }}/create-procedure.md %}#create-a-stored-procedure-that-uses-a-while-loop).
 
-### `EXIT` and `CONTINUE` statements
+### Control execution flow
+
+#### `EXIT`
 
 Add an `EXIT` statement to end a [loop](#write-loops). An `EXIT` statement can be combined with an optional `WHEN` boolean condition. 
 
@@ -299,6 +308,18 @@ CREATE PROCEDURE p() AS $$
   $$ LANGUAGE PLpgSQL;
 ~~~
 
+#### `RETURN`
+
+Add a `RETURN` statement to a routine with an `OUT` parameter or `VOID` return type to exit the routine immediately.
+
+~~~ sql
+BEGIN
+	...
+	RETURN;
+~~~
+
+#### `CONTINUE`
+
 Add a `CONTINUE` statement to end the current iteration of a [loop](#write-loops), skipping any statements below `CONTINUE` and beginning the next iteration of the loop. 
 
 A `CONTINUE` statement can be combined with an optional `WHEN` boolean condition. In the following example, if a `WHEN` condition is defined and met, then `CONTINUE` causes the loop to skip the second group of statements and begin again.
@@ -459,6 +480,14 @@ BEGIN
   END
 ~~~
 
+`WHEN` conditions are not required to execute statements. You can exclude any statements or add a placeholder `NULL` statement.
+
+~~~ sql
+EXCEPTION
+	WHEN error THEN
+		NULL;
+~~~
+
 ### Control transactions
 
 Use a `COMMIT` or `ROLLBACK` statement within a PL/pgSQL [stored procedure]({% link {{ page.version.version }}/stored-procedures.md %}) to finish the current transaction and automatically start a new one.