Difference between revisions of "String over columns"

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Line 4: Line 4:
 
<source lang=sql class='tidy'>DROP TABLE bedroom</source>
 
<source lang=sql class='tidy'>DROP TABLE bedroom</source>
 
<source lang=sql class='setup'> CREATE TABLE bedroom(
 
<source lang=sql class='setup'> CREATE TABLE bedroom(
   name VARCHAR(20)),
+
   name VARCHAR(20),
 
   floorcolor VARCHAR (20),
 
   floorcolor VARCHAR (20),
 
   ceilingcolor VRACHAR(20),
 
   ceilingcolor VRACHAR(20),

Revision as of 11:26, 30 July 2012

Search for a string across columns

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