LEFT JOIN
This type of JOIN
is used when you want to select records that are available in the first table and match records in the second one. It can be represented with the following Venn diagram:
The LEFT JOIN
represents the highlighted section from TABLE A and the intersected section from TABLE B. Let's look at the syntax:
SELECT [Column List] FROM [Table 1] LEFT OUTER JOIN [Table 2] ON [Table 1 Column Name] = [Table 2 Column Name] WHERE [Condition]
The syntax can also be as follows:
SELECT [Column List] FROM [Table 1] LEFT JOIN [Table 2] ON [Table 1 Column Name] = [Table 2 Column Name] WHERE [Condition]
Note
The OUTER
word in the query is optional.
This type of join is very similar to the RIGHT JOIN
, with the only difference being that it executes the table on the opposite (left) side. Now that we have seen how we can implement LEFT JOIN...