How Can I Retrieve SQL Server Data Using Column Ordinal Position When Direct Access Is Not Supported?

Retrieving SQL Server Data Using Column Ordinal Position

While using ordinal positions for column selection is generally discouraged, there may be scenarios where it is necessary for specific tasks, such as one-off data import processes. Consider the following example:

create table Test(
    Col1 int,
    Col2 nvarchar(10)
)

Instead of using the traditional syntax:

select Col2 from Test

It may be desirable to use ordinal positions to access column data:

select "2" from Test -- for illustration purposes only

Unfortunately, this approach is not supported in SQL Server. However, if the number of columns is known, a workaround can be employed:

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 results in an empty table with two pre-defined columns named [C1] and [C2]. The data from the Test table can then be unioned into this empty table, ensuring that the columns align correctly.

This method is not particularly useful for tables with a large number of columns. However, it can be a convenient solution for tables with a predetermined number of columns.

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