vectorwise 支持first和fetch first语法

显示全部楼层 · 2012-5-21 10:19:41

千问 · 2012-5-21 10:19:41

本帖最后由〇〇于 2012-9-23 08:34 编辑
postgersql也支持limit和fetch rows only
C:\Users\db2admin\pgsql\bin>psql test_en
psql (9.2.0)
输入 "help" 来获取帮助信息.
test_en=# select r_regionkey,r_name from region order by r_name limit 3\g
r_regionkey |
r_name
-------------+---------------------------
0 | AFRICA
1 | AMERICA
2 | ASIA
(3 行记录)

test_en=# select first 3 r_regionkey,r_name from region order by r_name\g
错误:语法错误在 "3" 或附近的
第1行select first 3 r_regionkey,r_name from region order by r_nam...

^
test_en=# select r_regionkey,r_name from region order by r_name fetch first 3 rows only\g
r_regionkey |
r_name
-------------+---------------------------
0 | AFRICA
1 | AMERICA
2 | ASIA
(3 行记录)
test_en=# select top 3 r_regionkey,r_name from region order by r_name\g
错误:语法错误在 "3" 或附近的
第1行select top 3 r_regionkey,r_name from region order by r_name

千问 · 2012-5-21 10:19:41

mysql只支持limit
mysql> select r_regionkey,r_name from region order by r_name limit 3\g
+-------------+---------+
| r_regionkey | r_name|
+-------------+---------+
| 0 | AFRICA|
| 1 | AMERICA |
| 2 | ASIA|
+-------------+---------+
3 rows in set (2.48 sec)
mysql> select first 3 r_regionkey,r_name from region order by r_name\g
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version
for the right syntax to use near '3 r_regionkey,r_name from region order by r_name' at line 1
mysql> select r_regionkey,r_name from region order by r_name fetch first 3 rows\g
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version
for the right syntax to use near 'fetch first 3 rows' at line 1
mysql>
mysql> select r_regionkey,r_name from region order by r_name fetch first 3 rows only\g
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version
for the right syntax to use near 'fetch first 3 rows only' at line 1
mysql> select top 3 r_regionkey,r_name from region order by r_name\g
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version
for the right syntax to use near '3 r_regionkey,r_name from region order by r_name' at line 1
mysql>