String over columns

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Revision as of 10:33, 30 July 2012 by Connor (Talk | contribs)

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Search for a string across columns

schema:scott
DROP TABLE bedrooms
 CREATE TABLE bedrooms(
  name VARCHAR(20),
  floorcolor VARCHAR(20),
  ceilingcolor VRACHAR(20),
  wallcolor VARCHAR(20));
INSERT INTO bedrooms VALUES ('Jim','RED','GREEN','YELLOW');
INSERT INTO bedrooms VALUES ('Bob','YELLOW','BLUE','BLACK');
INSERT INTO bedrooms VALUES ('Allan','BLUE','PINK','BLACK');
INSERT INTO bedrooms VALUES ('George','BLUE','GREEN','OAK');
SELECT name FROM bedrooms
WHERE floorcolor = 'YELLOW'
OR ceilingcolor = 'YELLOW'
OR wallcolor = 'YELLOW'

Using OR increases the chances for careless mistakes instead CONCAT could be used to make the query more efficient. To avoid problems make sure to add in separators and if a value cna be null make sure to use it is wrapped in COALESCE OR NVL for example: COALESCE(floorcolor,).

SELECT name FROM bedrooms
WHERE CONCAT (':',floorcolor,':',ceilingcolor,':',wallcolor,':')
LIKE '%:YELLOW:%'
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