Hi All,
Just came across a peculiar way of specifying only the column scale and not its precision, so thought of sharing with all. It looks pretty simple but could be a handy tip for table designs.
Scenario: Create a table CONT_EMPS where Salary column must store values upto 2 places of decimals (i.e. scale is 2). Here, note that no precision has been specified for the Salary column. Lets see how to do it.
SQL> CREATE TABLE CONT_EMPS
2 (EMPID NUMBER,
3 EMPNAME VARCHAR2(256),
4 SAL NUMBER(*,2))
5 /
Table created.
SQL> DESC CONT_EMPS
Name Null? Type
------------ -------- ----------------------------
EMPID NUMBER
EMPNAME VARCHAR2(256)
SAL NUMBER(38,2)
When I specify ‘*’ in place of precision, Oracle treats it as the maximum precision allowed for the column. Additionally, this convention doesn’t applies to PL/SQL data type declaration.
Bye for now.
Saurabh
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Good to know. Is it specific to oracle only or any database?
Posted by Sivasankar | November 17, 2011, 3:17 pmHI Saurabh,
Thanks for the post……
well @siva, just tested Saurabh post on 10g.It worked fine
Posted by srinivasaithagani | November 17, 2011, 11:38 pmHi Siva
SQL Server supports number datatype precision upto 38 digits. MySQL supports its till 65 digits.
As per Oracle documentation, Oracle supports the portability of numbers with precision equal or less than 38 digits. Therefore, reg the mentioned feature, I believe it is supported by Oracle only.
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Posted by Sammy | December 6, 2011, 3:55 amAppreciate it for helping out, great information.
Posted by Rhett Natal | December 17, 2011, 6:21 pm