SELECT

Description

Retrieves data from a table.

Syntax

  1. SELECT
  2.     [ALL | DISTINCT ]
  3.     select_expr [, select_expr] [[AS] alias] ...
  4.     [INTO variable [, ...]]
  5.     [FROM table_references
  6.     [WHERE where_condition]
  7.     [GROUP BY {col_name | expr | position}
  8.       [ASC | DESC]]
  9.     [HAVING where_condition]
  10.     [ORDER BY {col_name | expr | position}
  11.       [ASC | DESC]]
  12.     [LIMIT {[offset,] row_count | row_count OFFSET offset}]

Examples

  1. > SELECT number FROM numbers(3);
  2. +--------+
  3. | number |
  4. +--------+
  5. |      0 |
  6. |      1 |
  7. |      2 |
  8. +--------+
  10. > SELECT * FROM t1 WHERE spID>2 AND userID <2 || userID >=2 OR userID < 2 LIMIT 3;
  12. > SELECT userID,MAX(score) max_score FROM t1 WHERE userID <2 || userID > 3 GROUP BY userID ORDER BY max_score;
  14. > create table t1 (spID int,userID int,score smallint);
  15. > insert into t1 values (1,1,1);
  16. > insert into t1 values (2,2,2);
  17. > insert into t1 values (2,1,4);
  18. > insert into t1 values (3,3,3);
  19. > insert into t1 values (1,1,5);
  20. > insert into t1 values (4,6,10);
  21. > insert into t1 values (5,11,99);
  22. > select userID,count(score) from t1 group by userID having count(score)>1 order by userID;
  23. +--------+--------------+
  24. | userid | count(score) |
  25. +--------+--------------+
  26. |      1 |            3 |
  27. +--------+--------------+
  28. > select userID,count(score) from t1 where userID>2 group by userID having count(score)>1 order by userID;
  29. Empty set (0.01 sec)s

Constraints

  1. Table alias is not supported in GROUP BY.
  2. SELECT…FOR UPDATE clause is not supported now.
  3. INTO OUTFILE is limitedly support.