How Can Dynamic SQL Simulate SELECT * EXCEPT in SQL Server for Debugging?

*Dynamic SQL: A Workaround for SELECT EXCEPT in SQL Server Debugging**

While SELECT * is generally discouraged in production code, it can be helpful during debugging. However, SQL Server doesn't offer a direct "SELECT * EXCEPT" clause. This limitation can be overcome using dynamic SQL.

Let's say we want to retrieve all columns from the MY_Table table except the "description" column. Here's how to do it with dynamic SQL:

<code class="language-sql">DECLARE @sql VARCHAR(8000),
        @table_id INT,
        @col_id INT;

SET @sql = 'SELECT ';

SELECT @table_id = id FROM sysobjects WHERE name = 'MY_Table';

SELECT @col_id = MIN(colid) FROM syscolumns WHERE id = @table_id AND name <> 'description';

WHILE (@col_id IS NOT NULL)
BEGIN
    SELECT @sql = @sql + name FROM syscolumns WHERE id = @table_id AND colid = @col_id;

    SELECT @col_id = MIN(colid) FROM syscolumns WHERE id = @table_id AND colid > @col_id AND name <> 'description';
    IF (@col_id IS NOT NULL)
        SET @sql = @sql + ',';
    PRINT @sql;
END;

SET @sql = @sql + ' FROM MY_table';

EXEC (@sql);</code>

This code dynamically builds a SELECT statement by iterating through the table's columns and appending only those that aren't "description" to the query. This effectively simulates the desired "SELECT * EXCEPT" behavior. This approach can be encapsulated within a function or stored procedure for reusability. Remember, this method is intended solely for debugging in non-production environments due to its inherent limitations and security considerations.

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