Add doc example and test for limit+offset

Author: junli1026

tests/suites/0_stateless/03_0010_select_limit_offset.result

@@ -20,3 +20,9 @@
 17
 18
 19
+=== Test offset ===
+5
+6
+7
+8
+9

tests/suites/0_stateless/03_0010_select_limit_offset.sql

@@ -2,3 +2,5 @@ select '=== Test limit ===';
 select number from numbers_mt(100) order by number asc limit 10;
 select '=== Test limit with offset ===';
 select number from numbers_mt(100) order by number asc limit 10 offset 10;
+select '=== Test offset ===';
+select number from numbers_mt(10) order by number asc offset 5;

website/databend/docs/sqlstatement/data-manipulation-language-dml/dml-select.md

@@ -19,6 +19,7 @@ SELECT
     [HAVING expr]
     [ORDER BY {col_name | expr} [ASC | DESC], ...]
     [LIMIT row_count]
+    [OFFSET row_count]
     ]
 ```
 
@@ -144,6 +145,29 @@ mysql> SELECT number FROM numbers(1000000000) LIMIT 1;
 |      0 |
 +--------+
 1 row in set (0.00 sec)
+
+mysql> SELECT number FROM numbers(100000) ORDER BY number LIMIT 2 OFFSET 10;
++--------+
+| number |
++--------+
+|     10 |
+|     11 |
++--------+
+2 rows in set (0.02 sec)
+```
+
+## OFFSET clause
+
+```
+mysql> SELECT number FROM numbers(5) ORDER BY number OFFSET 2;
++--------+
+| number |
++--------+
+|      2 |
+|      3 |
+|      4 |
++--------+
+3 rows in set (0.02 sec)
 ```
 
 ## Nested Sub-Selects