1

I am now learning Oracle PL*SQL and having some understanding difficulties on dummy table which is called DUAL Table. Can someone explain what that is in a simple way? Please.

Brian Tompsett - 汤莱恩
  • 5,753
  • 72
  • 57
  • 129
Dilshad Abduwali
  • 1,388
  • 7
  • 26
  • 47
  • 1
    possible duplicate of [What is the use of DUAL table in Oracle?](http://stackoverflow.com/questions/4310851/what-is-the-use-of-dual-table-in-oracle) – Sathyajith Bhat Apr 16 '13 at 11:47
  • 2
    possible duplicate of [What is the dual table in Oracle?](http://stackoverflow.com/questions/73751/what-is-the-dual-table-in-oracle) – John Y Dec 02 '13 at 21:14

1 Answers1

3

Clean and simple explanation @ http://en.wikipedia.org/wiki/DUAL_table

The DUAL table is a special one-row, one-column table present by default in Oracle and other database installations. In Oracle, the table has a single VARCHAR2(1) column called DUMMY that has a value of 'X'. It is suitable for use in selecting a pseudo column such as SYSDATE or USER.

ROMANIA_engineer
  • 54,432
  • 29
  • 203
  • 199
harsh
  • 7,502
  • 3
  • 31
  • 32