Can I Select SQL Server Data Using Column Ordinal Position Instead of Column Names?

Selecting SQL Server Data Using Column Ordinal Position

While using ordinal positions for column selection is generally discouraged, it may be necessary for specific scenarios such as data import processes. Is it possible to retrieve column data using the ordinal position instead of specifying the column name?

Answer

Although it's not recommended to use ordinal positions directly in queries, there is a workaround that can be useful for tables with a predefined and small number of columns:

select NULL as C1, NULL as C2 where 1 = 0 
-- Returns empty table with predefined column names
union all
select * from Test 
-- There should be exactly 2 columns, but names and data type doesn't matter

This query will create a temporary table with two columns, [C1] and [C2], and then append all rows from the Test table to it. This allows you to access the second column of the Test table using the ordinal position 2, which is equivalent to the "2" in the illustrative query.

Note that if the number of columns in the Test table changes or if the data types are different, this workaround may not work correctly. Therefore, it's important to use named columns whenever possible to avoid potential issues.

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