sqlplus显示查询结果自动换行问题

今天做了个测试，中途发现有一列的显示总是自动换行

hr@ORCL> select sql_text,parse_calls,loads from v$sql where sql_text like 'select count(*) from employees';

SQL_TEXT

------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------

PARSE_CALLS      LOADS

----------- ----------

select count(*) from employees

          6          1

尝试设置了linesize后还是不行，群里咨询了下，同学提示是sql_text的显示长度过长导致

hr@ORCL> col sql_text for a50;

hr@ORCL> select sql_text,parse_calls,loads from v$sql where sql_text like 'select count(*) from employees';

SQL_TEXT                                           PARSE_CALLS      LOADS

-------------------------------------------------- ----------- ----------

select count(*) from employees                               6          1

总结：

col   =>column

for   =>formate

50   =>显示长度为50

字段的显示长度应该和字段类型有关(sql_text   varchar2(1000))但又不完全相等(猜测)

col还有更多用法，但基本都用不到，这里就不介绍了