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

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 without specifying all the columns?

SELECT * [except columnA] FROM tableA

The only way that I know is to manually specify all the columns and exclude the unwanted column. This is really time consuming so I'm looking for ways to save time and effort on this, as well as future maintenance should the table has more/less columns.

It would be very convenient to have this feature, not to put in production code, but for troubleshooting purposes. Example: I have a table that has several columns I query, but I want to quickly omit a text column or two.
I'd like to add another reason to do this: SELECT DISTINCT * except for the key column to work without duplicate rows someone else created
I agree that it is time consuming. This is why I usually just right click on the table, choose "select top 1000 rows", then remove the columns that I don't want.
not to forget: in many cases the developer does not know the columns because they can change. this is typical in data warehouses. after 6 months, they add an additional column and it should be selected without changing the code.
There are so many use cases for such a feature (exclude n columns from a SELECT *, as opposed to 1 column), it really ought to be added to the ANSI standard for SQL.

N
Nicolas Gervais

You can try it this way:

/* Get the data into a temp table */
SELECT * INTO #TempTable
FROM YourTable
/* Drop the columns that are not needed */
ALTER TABLE #TempTable
DROP COLUMN ColumnToDrop
/* Get results and drop temp table */
SELECT * FROM #TempTable
DROP TABLE #TempTable

Inefficient...but very creative :)
Beautiful. I often need to include join two temp tables or a temp to another table where I don't need all the columns in the temp - especially because grouping will be involved.
Very nice. Sure solves the problem of abstracting out the column names.
@CeesTimmerman - if you have a query involving duplicate column names, that is a separate problem, REGARDLESS of which approach you are taking. Google "SQL column rename" or "SQL column alias". Something like SELECT table1.ID AS table1ID ..., IIRC.
@ToolmakerSteve The idea of this question is to only specify columns you don't need. Naming columns would require specifying all, say, 20+ columns of a particular table.
d
demoncodemonkey

No.

Maintenance-light best practice is to specify only the required columns.

At least 2 reasons:

This makes your contract between client and database stable. Same data, every time

Performance, covering indexes

Edit (July 2011):

If you drag from Object Explorer the Columns node for a table, it puts a CSV list of columns in the Query Window for you which achieves one of your goals


there are valid scenarios with SELECT *, especially in ETL routines. I think the best answer here is the one with dynamic SQL.
There are cases where you want to select say all data for a student for statistical exploration but not bring down the wire the student id itself to bolster privacy
if for nothing else, i am glad i read this post to find out about the CSV trick. that is why giving background and info around the subject is important than just straight answers. +1 from me for that. thanks
Although answers like this get a lot of votes, they have no value as far as I'm concerned. Conceptually, being able to "Select * Except ABC" is no more problematic that "Select *" which the language does support. The OP is clearly asking for a way to accomplish something. The person answering this question has no way of knowing if the OP wants to use this in production code or if they just have an immediate need to run a query like this while they are developing some code for the database, so the lecture about good standards contributes no value at all.
Not so easy when the column list is dynamic.
H
Himanshu

If you don't want to write each column name manually you can use Script Table As by right clicking on table or view in SSMS like this:

https://i.stack.imgur.com/hjxWj.png

Then you will get whole select query in New Query Editor Window then remove unwanted column like this:

https://i.stack.imgur.com/g1gLL.png

Done


This is more easy than selecting all column names then add commas to it.
What GUI program are you assuming here?
@wheredidthatnamecomefrom: It's SSMS and that's not an assumption.
I must not be seeing where that was explained Thanks.
C
Community

The automated way to do this in SQL (SQL Server) is:

declare @cols varchar(max), @query varchar(max);
SELECT  @cols = STUFF
    (
        ( 
            SELECT DISTINCT '], [' + name
            FROM sys.columns
            where object_id = (
                select top 1 object_id from sys.objects
                where name = 'MyTable'
            )
            and name not in ('ColumnIDontWant1', 'ColumnIDontWant2')
            FOR XML PATH('')
        ), 1, 2, ''
    ) + ']';

SELECT @query = 'select ' + @cols + ' from MyTable';  
EXEC (@query);

What if you are querying from the result of a CTE or other subquery? A simple example: you might want to make a subquery that appends the result of row_number() to each row, then perform a join by row_number, then select everything excluding the row_number from the result of the join.
Y
Yves M.

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


At first my reaction was "how is this easier than just specifying the columns"? But then I decided that from a maintenance perspective, it might be an improvement.
This also supports the query optimiser rather than counteracting it with a temp table or dynamic SQL.
@ToolmakerSteve Also if you're doing a lot of different queries with that one column omitted, select * from the view could save you a lot of typing (and like you said, for maintenance, if you want to change that column set all around, e.g. you've added a new column, you just have to do it in the view and you can leave your queries alone). I actually go pretty heavy on views when possible in most applications, just to keep the application's SQL as short as I can.
V
Velizar VESSELINOV

A modern SQL dialect like BigQuery proposes an excellent solution.

SELECT * EXCEPT(ColumnNameX, [ColumnNameY, ...])
FROM TableA

This is a very powerful SQL syntax to avoid a long list of columns that need to be updated all the time due to table column name changes. And this functionality is missing in the current SQL Server implementation, which is a pity. Hopefully, one day, Microsoft Azure will be more data scientist-friendly.

Data scientists like to have a quick option to shorten a query and remove some columns (due to duplication or any other reason).

https://cloud.google.com/bigquery/docs/reference/standard-sql/query-syntax#select-modifiers


Oh, that's a great one. Thank you!
This is perfect! Thanks!
Why is this not the chosen answer!? Any moderators out there?
A
Anthony Faull

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:

Declare a variable to store a comma separated list of column names. This defaults to NULL. Use a system view to determine the names of the columns in our table. 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. 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. Use the WHERE clause to hide columns we don't want to see. 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.


I have one question: for which reason the second select has to be put into an EXEC statement? I have seen that it is effectively necessary, but I wonder why I cannot simply write SELECT @columns FROM contact
T
Tom H

Like the others have said there is no way to do this, but if you're using Sql Server a trick that I use is to change the output to comma separated, then do

select top 1 * from table

and cut the whole list of columns from the output window. Then you can choose which columns you want without having to type them all in.


See my tip about dragging from SSMS
m
marc_s

Basically, you cannot do what you would like - but you can get the right tools to help you out making things a bit easier.

If you look at Red-Gate's SQL Prompt, you can type "SELECT * FROM MyTable", and then move the cursor back after the "*", and hit <TAB> to expand the list of fields, and remove those few fields you don't need.

It's not a perfect solution - but a darn good one! :-) Too bad MS SQL Server Management Studio's Intellisense still isn't intelligent enough to offer this feature.......

Marc


This is good, but the problem is your query can become huge. It would be nice to have the "except" feature, not for prod code, but ad-hoc querying.
A
Ali Kazmi

no there is no way to do this. maybe you can create custom views if that's feasible in your situation

EDIT May be if your DB supports execution of dynamic sql u could write an SP and pass the columns u don't want to see to it and let it create the query dynamically and return the result to you. I think this is doable in SQL Server atleast


It is doable but I would fire the person doing that.
Classic cleanup problem: Copy the dfata you want to keep into a temp table, truncate the big one, re-fill with the temp table. You need to exclude the identity column.
@LievenKeersmaekers What?
@m4heshd - a bit too strong worded. It was 13 years ago and I was even more foolish back then but while this answer is a good theoretical excercise, I would not want anyone on my team spending actual valuable time implementing this. Cost/benefit can't (imho) be justified.
B
Bartosz X
DECLARE @SQL VARCHAR(max), @TableName sysname = 'YourTableName'

SELECT @SQL = COALESCE(@SQL + ', ', '') + Name 
FROM sys.columns
WHERE OBJECT_ID = OBJECT_ID(@TableName)
AND name NOT IN ('Not This', 'Or that');

SELECT @SQL = 'SELECT ' + @SQL + ' FROM ' + @TableName

EXEC (@SQL)

UPDATE:

You can also create a stored procedure to take care of this task if you use it more often. In this example I have used the built in STRING_SPLIT() which is available on SQL Server 2016+, but if you need there are pleanty of examples of how to create it manually on SO.

CREATE PROCEDURE [usp_select_without]
@schema_name sysname = N'dbo',
@table_name sysname,
@list_of_columns_excluded nvarchar(max),
@separator nchar(1) = N','
AS
BEGIN
 DECLARE 
 @SQL nvarchar(max),
 @full_table_name nvarchar(max) = CONCAT(@schema_name, N'.', @table_name);

 SELECT @SQL = COALESCE(@SQL + ', ', '') + QUOTENAME([Name])
 FROM sys.columns sc
 LEFT JOIN STRING_SPLIT(@list_of_columns_excluded, @separator) ss ON sc.[name] = ss.[value]
 WHERE sc.OBJECT_ID = OBJECT_ID(@full_table_name, N'u')
 AND ss.[value] IS NULL;

 SELECT @SQL = N'SELECT ' + @SQL + N' FROM ' + @full_table_name;
 EXEC(@SQL)
END

And then just:

EXEC [usp_select_without] 
@table_name = N'Test_Table',
@list_of_columns_excluded = N'ID, Date, Name';

s
shA.t

If you are using SQL Server Management Studio then do as follows:

Type in your desired tables name and select it Press Alt+F1 o/p shows the columns in table. Select the desired columns Copy & paste those in your select query Fire the query.

Enjoy.


S
Shrage Smilowitz

In summary you cannot do it, but I disagree with all of the comment above, there "are" scenarios where you can legitimately use a * When you create a nested query in order to select a specific range out of a whole list (such as paging) why in the world would want to specify each column on the outer select statement when you have done it in the inner?


Can you use some variation of "innername.*" to represent the inner columns, similar to "SELECT table1.* ..." when doing a join?
c
cjk

In SQL Management Studio you can expand the columns in Object Explorer, then drag the Columns tree item into a query window to get a comma separated list of columns.


This answer is way too underrated. This is the easiest and quickest way.
s
shA.t

If you want to exclude a sensitive case column like the password for example, I do this to hide the value :

SELECT * , "" as password FROM tableName;

While you should of course never store clear-text passwords in your database. At least they should be hashed with salt and maybe pepper security.stackexchange.com/questions/3272/…
Getting An object or column name is missing or empty. For SELECT INTO statements, verify each column has a name. For other statements, look for empty alias names. Aliases defined as "" or [] are not allowed. Change the alias to a valid name. on this one
Did you test this? Traditionally in SQL, this would still show the original password column and then a new column called password with a blank string. They can even have the same name. In a simple select query, your blank column won't override the original. And in a table or view creation, it will give an error for duplicate column names.
N
Nadeem_MK

If we are talking of Procedures, it works with this trick to generate a new query and EXECUTE IMMEDIATE it:

SELECT LISTAGG((column_name), ', ') WITHIN GROUP (ORDER BY column_id)
INTO var_list_of_columns
FROM ALL_TAB_COLUMNS
WHERE table_name = 'PUT_HERE_YOUR_TABLE'
AND column_name NOT IN ('dont_want_this_column','neither_this_one','etc_column');

o
onedaywhen

Is there a way to exclude column(s) from a table without specifying all the columns?

Using declarative SQL in the usual way, no.

I think your proposed syntax is worthy and good. In fact, the relational database language 'Tutorial D' has a very similar syntax where the keywords ALL BUT are followed by a set of attributes (columns).

However, SQL's SELECT * already gets a lot a flak (@Guffa's answer here is a typical objection), so I don't think SELECT ALL BUT will get into the SQL Standard anytime soon.

I think the best 'work around' is to create a VIEW with only the columns you desire then SELECT * FROM ThatView.


@underscore_d: I've now revised my answer.
Cool, I agree with your last 2 paragraphs. The info about Tutorial D is interesting, although I tend to agree with those who think select * is questionable - very useful for ad hoc stuff and programs that need to generically handle data tables, but not so much for building (in lack of a better word) 'pure' queries. Still, not being in the ANSI standard doesn't mean Microsoft can't add it to their dialect, as with many other things, but I'm sceptical whether they would.
M
Mahesh Madushanka

The best way to solve this is using view you can create view with required columns and retrieve data form it

example

mysql> SELECT * FROM calls;
+----+------------+---------+
| id | date       | user_id |
+----+------------+---------+
|  1 | 2016-06-22 |       1 |
|  2 | 2016-06-22 |    NULL |
|  3 | 2016-06-22 |    NULL |
|  4 | 2016-06-23 |       2 |
|  5 | 2016-06-23 |       1 |
|  6 | 2016-06-23 |       1 |
|  7 | 2016-06-23 |    NULL |
+----+------------+---------+
7 rows in set (0.06 sec)

mysql> CREATE VIEW C_VIEW AS
    ->     SELECT id,date from calls;
Query OK, 0 rows affected (0.20 sec)

mysql> select * from C_VIEW;
+----+------------+
| id | date       |
+----+------------+
|  1 | 2016-06-22 |
|  2 | 2016-06-22 |
|  3 | 2016-06-22 |
|  4 | 2016-06-23 |
|  5 | 2016-06-23 |
|  6 | 2016-06-23 |
|  7 | 2016-06-23 |
+----+------------+
7 rows in set (0.00 sec)

What if the number of columns is large, say 100 & we wanted to SELECT all columns, but one. Is there a better approach?
This one kind of misses the point. You are selecting "id,date" in the second call, which, if you were going to do that, just do it in the first place.
R
Ronald Wildenberg

I do not know of any database that supports this (SQL Server, MySQL, Oracle, PostgreSQL). It is definitely not part of the SQL standards so I think you have to specify only the columns you want.

You could of course build your SQL statement dynamically and have the server execute it. But this opens up the possibility for SQL injection..


u
user3393089

Postgres sql has a way of doing it

pls refer: http://www.postgresonline.com/journal/archives/41-How-to-SELECT-ALL-EXCEPT-some-columns-in-a-table.html

The Information Schema Hack Way

SELECT 'SELECT ' || array_to_string(ARRAY(SELECT 'o' || '.' || c.column_name
        FROM information_schema.columns As c
            WHERE table_name = 'officepark' 
            AND  c.column_name NOT IN('officeparkid', 'contractor')
    ), ',') || ' FROM officepark As o' As sqlstmt

The above for my particular example table - generates an sql statement that looks like this

SELECT o.officepark,o.owner,o.squarefootage FROM officepark As o


i
imz -- Ivan Zakharyaschev

I know this is a little old, but I had just run into the same issue and was looking for an answer. Then I had a senior developer show me a very simple trick.

If you are using the management studio query editor, expand the database, then expand the table that you are selecting from so that you can see the columns folder.

In your select statement, just highlight the referenced columns folder above and drag and drop it into the query window. It will paste all of the columns of the table, then just simply remove the identity column from the list of columns...


Yes, but what if you have 5 joins, the idea would be to do SELECT * Except(tableName.ColumnName) FROM ...
I find this useful :) I haven't known about that, nevertheless this is not an answer for topic question.
G
Gustavo

Well, it is a common best practice to specify which columns you want, instead of just specifying *. So you should just state which fields you want your select to return.


c
cairnz

Right click table in Object Explorer, Select top 1000 rows

It'll list all columns and not *. Then remove the unwanted column(s). Should be much faster than typing it yourself.

Then when you feel this is a bit too much work, get Red Gate's SQL Prompt, and type ssf from tbl, go to the * and click tab again.


C
Charl

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.


J
JustSomeGuy

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


V
Vladimir Djuricic

I did it like this and it works just fine (version 5.5.41):

# prepare column list using info from a table of choice
SET @dyn_colums = (SELECT REPLACE(
GROUP_CONCAT(`COLUMN_NAME`), ',column_name_to_remove','') 
FROM `INFORMATION_SCHEMA`.`COLUMNS` WHERE 
`TABLE_SCHEMA`='database_name' AND `TABLE_NAME`='table_name');

# set sql command using prepared columns
SET @sql = CONCAT("SELECT ", @dyn_colums, " FROM table_name");

# prepare and execute
PREPARE statement FROM @sql;
EXECUTE statement;

s
spenibus

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

Consider elaborating/clarifying your question/problem.
J
Jiadong Chen

In Hive Sql you can do this:

set hive.support.quoted.identifiers=none;
select 
    `(unwanted_col1|unwanted_col2|unwanted_col3)?+.+`
from database.table

this gives you the rest cols


This regex is flawed. If you want to exclude two columns day and day_hour, (day|day_hour)?+.+ will still match day_hour column. That's because regex engine is eager on |. Although changing the order to (day_hour|day)?+.+ can solve this issue, the better method is using negative lookahead, (?!(day|day_hour)$).+.
J
John Ranger

The proposed answer (stored procedure) from BartoszX didn't work for me when using a view instead of a real table.

Credit for the idea and the code below (except for my fix) belongs to BartoszX.

In order that this works for tables as well as for views, use the following code:

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE PROCEDURE [dbo].[select_without]
@schema_name sysname = N'dbo',
@table_name sysname,
@list_of_columns_excluded nvarchar(max),
@separator nchar(1) = N','
AS
BEGIN
 DECLARE 
 @SQL nvarchar(max),
 @full_table_name nvarchar(max) = CONCAT(@schema_name, N'.', @table_name);

 SELECT @SQL = COALESCE(@SQL + ', ', '') + QUOTENAME([Name])
 FROM sys.columns sc
 LEFT JOIN STRING_SPLIT(@list_of_columns_excluded, @separator) ss ON sc.[name] = ss.[value]
 WHERE sc.OBJECT_ID = OBJECT_ID(@full_table_name)
 AND ss.[value] IS NULL;

 SELECT @SQL = N'SELECT ' + @SQL + N' FROM ' + @full_table_name;
 EXEC(@SQL)
END
GO

W
Weihui Guo

I know this question is old, but I hope this can still be helpful.The answer is inspired by a discuss from SQL Server Forums. You can make this a stored procedure. It can also be modified to add more than one except fields.

DECLARE @SQL NVARCHAR(MAX)
SELECT @SQL = COALESCE(@SQL + ', ', ' ' ) + name from sys.columns where name not in ('colName1','colName2') and object_id = (Select id from sysobjects where name = 'tblName')
SELECT @SQL = 'SELECT ' + @SQL + ' FROM ' + 'tblName'
EXEC sp_executesql  @SQL