Different approach of using IN clause in MySql

Question

Today I have posted an answer with a query like this

SELECT * FROM table_name where column_name IN (val1,val2,...)

Some another user has po

Answer 1

you raised a question that is connected with my answer here.

In a simple explanation using this statements below,

SELECT * FROM TableName WHERE column1 IN (1, 2, 3, 4)
-- versus
SELECT * FROM TableName WHERE 1 IN (column1, column2, column3, column4)

The first statement involves only ONE COLUMN that is being compared to multiple values.

SELECT  *
FROM   TableName
WHERE  column1 = 1 OR
       column1 = 2 OR
       column1 = 3 OR
       column1 = 4

while the second statement is A VALUE that is compared to multiple columns.

SELECT  *
FROM   TableName
WHERE  column1 = 1 OR
       column2 = 1 OR
       column3 = 1 OR
       column4 = 1

which is a bit different from one another.

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UPDATE 1

Here's the third form of IN clause:

• Multi-Column IN clause – Unexpected MySQL Issue