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文件名称：列头部的缺省格式-SQL语言基础
文件大小：5.26MB
文件格式：PPT
更新时间：2021-04-25 19:38:05
SQL 基础
列头部的缺省格式
缺省的对齐方式
左部对齐：日期、字符数据
右部对齐：数字格式数据
缺省的显示方式: 大写
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Column Heading Defaults
Character column heading and data as well as date column heading and data are left-justified within a column width. Number headings and data are right-justified.
Character and date column headings can be truncated, but number headings cannot be truncated. The column headings appear in uppercase by default. You can override the column heading display with an alias. Column aliases are covered later in this lesson.
SQL> SELECT ename, hiredate, sal
2 FROM emp;
ENAME HIREDATE SAL
---------- --------- ---------
KING 17-NOV-81 5000
BLAKE 01-MAY-81 2850
CLARK 09-JUN-81 2450
JONES 02-APR-81 2975
MARTIN 28-SEP-81 1250
ALLEN 20-FEB-81 1600
...
14 rows selected.