49.206.12.90 at 11:37, 12 March 2013

2013-03-12T11:37:04Z

49.206.12.90 at 11:36, 12 March 2013

2013-03-12T11:36:27Z

Connor: Created page with "

The SELECT .. LEFT JOIN statement

The LEFT JOIN will include rows from the left table even when the linking value is null.

..."

2012-07-17T09:23:02Z

Created page with " <h1>The SELECT .. LEFT JOIN statement</h1> <table class='NoBorder'><td><tr> The LEFT JOIN will include rows from the left table even when the linking value is null. </td><td>..."

New page

<h1>The SELECT .. LEFT JOIN statement</h1>
<table class='NoBorder'><td><tr>
The LEFT JOIN will include rows from the left table even when the linking value is null.
</td><td>
<table style='float:left' class='Bordered'>
<caption align='center'>'''games'''</caption>
<tr><th align='center'>'''yr'''</th><th align='center'>'''city'''</th></tr>
<tr><td>2004</td><td align='left'>Athens</td></tr>
<tr><td>2008</td><td align='left'>Beijing</td></tr>
<tr><td>2012</td><td align='left'>London</td></tr>
<tr><td>2032</td><td align='left'>null</td></tr>
</table>
</td><td>
<table style='float:left' class='Bordered'>
<caption>'''city'''</caption>
<tr><th align='center'>'''name'''</th><th align='center'>'''country'''</th></tr>
<tr><td align='left'>Sydney</td><td align='left'>Australia</td></tr>
<tr><td align='left'>Athens</td><td align='left'>Greece</td></tr>
<tr><td align='left'>Beijing</td><td align='left'>China</td></tr>
<tr><td align='left'>London</td><td align='left'>UK</td></tr>
</table>
</td></table>

<div class='ht'>
<div class=params>schema:scott</div>
<source lang=sql class='tidy'> DROP TABLE games;
DROP TABLE city</source>
<source lang=sql class='setup'> CREATE TABLE games(
yr INTEGER,
city VARCHAR(20));
INSERT INTO games VALUES (2004,'Athens');
INSERT INTO games VALUES (2008,'Beijing');
INSERT INTO games VALUES (2012,'London');
INSERT INTO games VALUES (2032,'');
CREATE TABLE city (
name VARCHAR(20),
country VARCHAR(20));
INSERT INTO city VALUES ('Sydney','Australia');
INSERT INTO city VALUES ('Athens','Greece');
INSERT INTO city VALUES ('Beijing','China');
INSERT INTO city VALUES ('London','UK');
</source>
There is no data on where the 2032 games will be held.
The LEFT JOIN will include a row for 2032 even though it has no corresponding city.
<source lang='sql' class='def e-oracle'>
SELECT games.yr, city.country
FROM scott.games LEFT JOIN scott.city
ON (games.city = city.name)
</source>
<source lang='sql' class='def'>
SELECT games.yr, city.country
FROM games LEFT JOIN city
ON (games.city = city.name)
</source>
</div>

<p>See also</p>
<ul>
<li>[[Using_Null |LEFT and RIGHT JOIN Tutorial]]</li>
<li>[[SELECT_.._JOIN |SELECT JOIN]]</li>
</ul>

@@ Line 10: / Line 10: @@
 <tr><td>2008</td><td align='left'>Beijing</td></tr>
 <tr><td>2012</td><td align='left'>London</td></tr>
-<tr><td>2032</td><td align='left'>ADITYA</td></tr>
+<tr><td>2032</td><td align='left'></td></tr>
 </table>
 </td><td>

LEFT JOIN - Revision history

49.206.12.90 at 11:37, 12 March 2013

49.206.12.90 at 11:36, 12 March 2013

Connor: Created page with "

The SELECT .. LEFT JOIN statement