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openGauss ORDER BY Clause

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霞 童
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The ORDER BY clause sorts the data in one or more columns retrieved by the SELECT statement in ascending (ASC) or descending (DESC) order.

Syntax

SELECT 
{ * | [column, ...] }
[ FROM from_item [, ...] ]
[ ORDER BY {expression [ ASC | DESC ] }];

Parameter Description

  • ORDER BY clause

    Sorts data retrieved by the SELECT statement in descending or ascending order. If the ORDER BY expression contains multiple columns:

    • If two columns are equal according to the leftmost expression, they are compared according to the next expression and so on.

    • If they are equal according to all specified expressions, they are returned in an implementation-dependent order.

Examples

  • Sort the result in ascending order based on the value of c_customer_sk.

      openGauss=# SELECT * FROM customer_t1 ORDER BY c_customer_sk ASC;
   c_customer_sk | c_customer_id | c_first_name | c_last_name | amount
  ---------------+---------------+--------------+-------------+--------
            3869 | hello         | Grace        |             |   1000
            3869 | hello         | Grace        |             |   1000
            3869 |               | Grace        |             |
            3869 | hello         |              |             |
            3869 | hello         |              |             |
            4421 | Admin         | Local        |             |   3000
            6985 | maps          | Joes         |             |   2200
            9976 | world         | James        |             |   5000
                 |               |              |             |
  (9 rows)

  • Sort the result in descending order based on the value of c_customer_sk.

      openGauss=# SELECT * FROM customer_t1 ORDER BY c_customer_sk DESC;
   c_customer_sk | c_customer_id | c_first_name | c_last_name | amount
  ---------------+---------------+--------------+-------------+--------
                 |               |              |             |
            9976 | world         | James        |             |   5000
            6985 | maps          | Joes         |             |   2200
            4421 | Admin         | Local        |             |   3000
            3869 | hello         | Grace        |             |   1000
            3869 | hello         |              |             |
            3869 | hello         | Grace        |             |   1000
            3869 |               | Grace        |             |
            3869 | hello         |              |             |
  (9 rows)
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