alias column

Jensen_hj — Thu, 10 Sep 2009 08:54:00 GMT

1. 为计算的列起别名

SQL> column ename   heading "Employee"
SQL> column sal     heading "Salary"
SQL> column raise   heading "Raise"

2.To_char function

SQL> select PRODUCT_NAME,
  2         to_char(PRODUCT_PRICE, '$9,999.00') "Price",
  3         to_char(QUANTITY_ON_HAND, '999,999') "On Hand",
  4         '  '|| to_char(LAST_STOCK_DATE, 'MON DD, YYYY') "Last Stocked"
  5  from   PRODUCT;

PRODUCT_NAME              Price      On Hand  Last Stocked
------------------------- ---------- -------- --------------
Small Widget                  $99.00        1   JAN 15, 2003
Medium Widget                 $75.00    1,000   JAN 15, 2002
Product Number                $50.00      100   JAN 15, 2003
Round Church Station          $25.00   10,000

3.TO_CHAR(last_stock_date, 'MM-DD-YYYY HH24:MI') with column alias

SQL> SELECT product_name,
  2         product_price,
  3         quantity_on_hand,
  4         TO_CHAR(last_stock_date, 'MM-DD-YYYY HH24:MI') "Last Stocked"
  5  FROM   product;

PRODUCT_NAME              PRODUCT_PRICE QUANTITY_ON_HAND Last Stocked
------------------------- ------------- ---------------- ----------------
Small Widget                         99                1 01-15-2003 00:00
Medium Widget                        75             1000 01-15-2002 00:00
Product Number                       50              100 01-15-2003 00:00
Round Church Station                 25            10000

Jensen_hj 2009-09-10 16:54 发表评论

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alias column