Shulou(Shulou.com)06/01 Report--

Restrict data access:

Use numbers as conditions

Select ename,sal,deptno from emp where DEPTNO=10

Use characters as conditions, the string should be quoted only, case-sensitive!

Select ename,sal,deptno from emp where ename='king'

Select ename,sal,deptno from emp where ename='KING'

Use date as a condition, format sensitive!

Select ename,hiredate from emp where hiredate='23-JAN-82'

View the system date format with the help of the system function:

Select sysdate from dual

Select * from nls_database_parameters

Use single-line comparison symbols in where conditions

>

=, = and

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