affiliate marketing Interview Qns: Escape Characters
Showing posts with label Escape Characters. Show all posts
Showing posts with label Escape Characters. Show all posts

Monday, October 25, 2010

How does one escape special characters when building SQL queries?

The LIKE keyword allows for string searches. The '_' wild card character is used to match exactly one character, '%' is used to match zero or more occurrences of any characters. These characters can be escaped in SQL.

Example:

SELECT name FROM emp WHERE id LIKE '%\_%' ESCAPE '\';

Use two quotes for every one displayed. Example:

SELECT 'Franks''s Oracle site' FROM DUAL;
SELECT 'A ''quoted'' word.' FROM DUAL;
SELECT 'A ''''double quoted'''' word.' FROM DUAL;