SQL SERVER – The Self Join
A self-join is joining a table to itself. This is done by using table name aliases to give each instance of the table a separate name. Self Join is very useful when you want to compare values in a column to other values in the same column.
Self join and its example is very common question in the interview.
Let us take a look to example
Self Join
Self Join
Self Join
Self Join
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Hi, The result showing only left columns in the table & in right column it is showing total Null values. What’s the reason for it?
Did you join sup_id on ID? 🙂
Yes … Any question ?