Pl sql what is dual

Wondering what it is? Find out what the dual table in Oracle is in this article. You might be wondering, why would we even use this DUAL table in the first place? Now, this is only Oracle-specific. Also helps you to check if Oracle is up and check sql syntax, etc. A utility table in Oracle with only 1 row and 1 column.

It is used to perform a number of arithmetic operations and can be used generally where one needs to generate a known output. It is always used to get the operating systems functions like date, time, arithmetic expression.

It's a object to put in the from that return 1 empty row. For example: select 1 from dual; returns 1. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. What is the dual table in Oracle? Ask Question. Asked 13 years, 1 month ago. Active 2 years, 6 months ago. Viewed k times. I've heard people referring to this table and was not sure what it was about. Improve this question. Asked 10 years, 10 months ago.

Active 4 years, 7 months ago. Viewed 60k times. Also, why don't I see the same behaviour when I create my own dual table? Improve this question. Joe 4, 1 1 gold badge 25 25 silver badges 37 37 bronze badges.

Lazer Lazer 3, 15 15 gold badges 37 37 silver badges 53 53 bronze badges. Add a comment. Active Oldest Votes. Improve this answer. Community Bot 1. Brian Ballsun-Stanton Brian Ballsun-Stanton 4, 2 2 gold badges 26 26 silver badges 36 36 bronze badges. I also can't agree that it shouldn't be used in production. That sounds like a "cut the ends off the roast" meme, to me.

This answer needs improvement as it disagrees with itself. In one place it copies from the official docs: "The dual table is useful " and in another it recommends "It shouldn't be used in production, unless If you insert one, you will see the same behavior.

Nick Chammas Hendrik Brummermann Hendrik Brummermann 1 1 gold badge 3 3 silver badges 15 15 bronze badges. This means, for example, you can describe the table. Erwin Brandstetter k 18 18 gold badges silver badges bronze badges.

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