SQL exclude a column using SELECT * [except columnA] FROM tableA?

Question

We all know that to select all columns from a table, we can use

SELECT * FROM tableA

Is there a way to exclude column(s) from a table witho

Answer 1

A colleage advised a good alternative:

• Do SELECT INTO in your preceding query (where you generate or get the data from) into a table (which you will delete when done). This will create the structure for you.
• Do a script as CREATE to new query window.
• Remove the unwanted columns. Format the remaining columns into a 1 liner and paste as your column list.
• Delete the table you created.

Done...

This helped us a lot.

Answer 2

Sometimes the same program must handle different database stuctures. So I could not use a column list in the program to avoid errors in select statements.

* gives me all the optional fields. I check if the fields exist in the data table before use. This is my reason for using * in select.

This is how I handle excluded fields:

Dim da As New SqlDataAdapter("select * from table", cn)
da.FillSchema(dt, SchemaType.Source)
Dim fieldlist As String = ""
For Each DC As DataColumn In DT.Columns
   If DC.ColumnName.ToLower <> excludefield Then
    fieldlist = fieldlist &  DC.Columnname & ","
   End If
  Next

Answer 3

Wouldn't it be simpler to do this:

sp_help <table_name>

-Click on the 'Column_name' column> Copy> Paste (creates a vertical list) into a New Query window and just type commas in front of each column value... comment out the columns you don't want... far less typing than any code offered here and still manageable.

Answer 4

You could create a view that has the columns you wish to select, then you can just select * from the view...

Answer 5

Yes it's possible (but not recommended).

CREATE TABLE contact (contactid int, name varchar(100), dob datetime)
INSERT INTO contact SELECT 1, 'Joe', '1974-01-01'

DECLARE @columns varchar(8000)

SELECT @columns = ISNULL(@columns + ', ','') + QUOTENAME(column_name)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'contact' AND COLUMN_NAME <> 'dob'
ORDER BY ORDINAL_POSITION

EXEC ('SELECT ' + @columns + ' FROM contact')

Explanation of the code:

1. Declare a variable to store a comma separated list of column names. This defaults to NULL.
2. Use a system view to determine the names of the columns in our table.
3. Use SELECT @variable = @variable + ... FROM to concatenate the column names. This type of SELECT does not not return a result set. This is perhaps undocumented behaviour but works in every version of SQL Server. As an alternative you could use SET @variable = (SELECT ... FOR XML PATH('')) to concatenate strings.
4. Use the ISNULL function to prepend a comma only if this is not the first column name. Use the QUOTENAME function to support spaces and punctuation in column names.
5. Use the WHERE clause to hide columns we don't want to see.
6. Use EXEC (@variable), also known as dynamic SQL, to resolve the column names at runtime. This is needed because we don't know the column names at compile time.

Answer 6

That what I use often for this case:

declare @colnames varchar(max)=''

select @colnames=@colnames+','+name from syscolumns where object_id(tablename)=id and name not in (column3,column4)

SET @colnames=RIGHT(@colnames,LEN(@colnames)-1)

@colnames looks like column1,column2,column5