SQL Statement indentation good practice [closed]

Answer 1

SELECT
    Column1,
    Column2
FROM
    Table1
WHERE
    Column3 IN
    (
        SELECT TOP (1)
            Column4
        FROM 
            Table2
        INNER JOIN 
            Table3
        ON
            Table2.Column1 = Table3.Column1
    )

Answer 2

Not sure there is an accepted practice, but here's now how I'd do it:

SELECT 
    column1, 
    column2 
FROM 
    table1 
WHERE 
    column3 IN 
    ( 
     SELECT TOP(1) 
         column4 
     FROM 
         table2 
         INNER JOIN 
         table3 
             ON table2.column1 = table3.column1 
    )

Answer 3

SELECT column1, column2
FROM table
WHERE column3 IN (
    SELECT TOP(1) column4
    FROM table2
    INNER JOIN table3 ON table2.column1 = table3.column1
)

This is pretty short and easy to read. I'd make adjustments if there were more columns selected or more join conditions.

Answer 4

Yeah, this is pretty subjective...But here's my 2 cents:

SELECT
   Column1,
   Column2
FROM Table1
WHERE 
   Column3 IN (
      SELECT Column4
      FROM Table2
      JOIN Table3 ON
         Table2.Column1 = Table3.Column1
   )

But, really, I'd probably rewrite it without the IN:

SELECT
   Column1,
   Column2
FROM Table1
JOIN Table2 ON
   Table1.Column3 = Table2.Column4
JOIN Table3 ON
   Table2.Column1 = Table3.Column1

Basically, my rules are:

• Capitalize Keywords
• Columns go on individual lines, but SELECT modifiers (SELECT TOP 100, SELECT DISTINCT, etc.) or single columns (SELECT 1, SELECT Id, SELECT *, etc.) go on same line
• Join conditions indented underneath JOIN clause
• Use JOIN for INNER JOIN (since it's the common one), and fully specify others (LEFT OUTER JOIN, FULL OUTER JOIN, etc.)
• Open parens on same line, close paren on separate line. If you have an alias, the alias goes with close paren.

Answer 5

Well, of course it depends on the query.

For simple queries, a highly formal indentation scheme is just more trouble than it's worth and can actually make the code less readable, not more. But as complexity grows you need to start being more careful with how you structure the statement, to make sure it will be readable again later.

Answer 6

I like to have the different parts of my query line up vertically. I tend to use a tab size of 8 spaces for SQL which seems to work well.

SELECT  column1, 
        column2
FROM    table1
WHERE   column3 IN
(
        SELECT TOP(1) column4
        FROM    table2
        INNER JOIN table3
        ON      table2.column1  = table3.column1
)