How to select some particular columns from a table if the table has more than 100 columns - sql

I need to select 90 columns out of 107 columns from my table.
Is it possible to write select * except( column1,column2,..) from table or any other way to get specific columns only, or I need to write all the 90 columns in select statement?

You could generate the column list:
select name + ', '
from sys.columns
where object_id = object_id('YourTable')
and name not in ('column1', 'column2')
It's possible to do this on the fly with dynamic SQL:
declare #columns varchar(max)
select #columns = case when #columns is null then '' else #columns + ', ' end +
quotename(name)
from sys.columns
where object_id = object_id('YourTable')
and name not in ('column1', 'column2')
declare #query varchar(max)
set #query = 'select ' + #columns + ' from YourTable'
exec (#query)

No, there's no way of doing * EXCEPT some columns. SELECT * itself should rarely, if ever, be used outside of EXISTS tests.
If you're using SSMS, you can drag the "columns" folder (under a table) from the Object Explorer into a query window, and it will insert all of the column names (so you can then go through them and remove the 17 you don't want)

There is no way in SQL to do select everything EXCEPT col1, col2 etc.
The only way to do this is to have your application handle this, and generate the sql query dynamically.

You could potentially do some dynamic sql for this, but it seems like overkill. Also it's generally considered poor practice to use SELECT *... much less SELECT * but not col3, col4, col5 since you won't get consistent results in the case of table changes.
Just use SSMS to script out a select statement and delete the columns you don't need. It should be simple.

No - you need to write all columns you need. You might create an view for that, so your actual statement could use select * (but then you have to list all columns in the view).

Since you should never be using select *, why is this a problem? Just drag the columns over from the Object Explorer and delete the ones you don't want.

Related

TSQL - Identify the table name as a column of the single or multiple tables in a select statement WITHOUT HARDCODING it as part of the query

I need to display the table name in my select statement.
select col1, table_name_1 as table_name from table_name_1
Which I insert into another table.
My problem is I have to do this dynamically not as explained by this question.
Display the table name in the select statement
Not sure if this available with a single key word like for an eg. the currentdate we could use something like GETDATE().
Thank you for your answer.
As you were told already, there is no special keyword, which you could use for an easy-cheesy solution. If you really need this, you would add the table's name as a parameter and use a dynamically created statement.
Another approach was a VIEW for each table you are looking for, something along this
CREATE VIEW Table1_withName AS
SELECT 'Table1' AS TableName, * FROM Table1 --use columns instead of "*"
You can use this VIEW instead of the table in all your selects. This is not without hardcoding, but you could even generate the code to create your views out of INFORMATION_SCHEMA.TABLES. And when you call the views, there is no special action needed.
You might use FOR XML AUTO...
There is a fully generic / ad-hoc approach too, but I doubt that this will help you:
Hint: I use - as example only - a TOP 3 * FROM sys.objects. This would work with your tables too.
--FOR XML AUTO will add the table's name as the element's name
SELECT TOP 3 * FROM sys.objects FOR XML AUTO
--result
<sys.objects name="sysrscols" object_id="3" ...
--In case you use an alias, this alias is used
SELECT TOP 3 * FROM sys.objects AnyAlias FOR XML AUTO
--You would have to change this a little, if you want to enforce to include NULL values.
--But this is element centric XML now, the one before was attribute centric.
SELECT TOP 3 * FROM sys.objects FOR XML AUTO,ELEMENTS XSINIL
--This is the way you could use this, to simulate the generic table's name
SELECT EachRow.value('local-name(.)','nvarchar(max)') AS TableName
,EachRow.value('./#name,','nvarchar(max)') AS name
,EachRow.value('./#object_id','int') AS object_id
,EachRow.value('./#schema_id','int') AS schema_id
--add all columns here
FROM
(
--Your original Statement goes here
SELECT TOP 3 * FROM sys.objects
FOR XML AUTO, TYPE
) A(TheSelectAsXml)
CROSS APPLY A.TheSelectAsXml.nodes('*') B(EachRow);
The result
TableName name object_id schema_id
sys.objects sysrscols 3 4
This would even work with joined sources. Try this one out:
SELECT TOP 3 * FROM sys.objects
INNER JOIN sys.all_columns ON sys.objects.object_id=sys.all_columns.object_id
FOR XML AUTO,TYPE
I don't think there is inbuilt function available in T-SQL other than OBJECT_NAME (object_id('TableName')) which required to hard-code Table name.
However, as workaround, following query could fulfill your requirements:
Declare #tbname varchar(50);
Declare #SelectQuery varchar(2000);
set #tbname = 'YourTable';
set #SelectQuery = 'select *, OBJECT_NAME (object_id(' + '''' + #tbname + '''' +')) from ' + #tbname;
--print #SelectQuery;
exec (#SelectQuery);

How to select all the columns of a table except one column?

How to select all the columns of a table except one column?
I have nearly 259 columns I cant mention 258 columns in SELECT statement.
Is there any other way to do it?
You can use this approach to get the data from all the columns except one:-
Insert all the data into a temporary table
Then drop the column which you dont want from the temporary table
Fetch the data from the temporary table(This will not contain the data of the removed column)
Drop the temporary table
Something like this:
SELECT * INTO #TemporaryTable FROM YourTableName
ALTER TABLE #TemporaryTable DROP COLUMN Columnwhichyouwanttoremove
SELECT * FROM #TemporaryTable
DROP TABLE #TemporaryTable
Create a view. Yes, in the view creation statement, you will have to list each...and...every...field...by...name.
Once.
Then just select * from viewname after that.
This is not a generic solution, but some databases allow you to use regular expressions to specify the columns.
For instance, in the case of Hive, the following query selects all columns except ds and hr:
SELECT `(ds|hr)?+.+` FROM sales
You can get the column name details from sys.columns table
Try the following query:
SELECT * FROM SYS.COLUMNS
WHERE object_id = OBJECT_ID('dbo.TableName')
AND [Name] <> 'ColumnName'
DECLARE #sql as VARCHAR(8000)
SET #sql = 'SELECT '
SELECT #sql += [Name] + ', ' FROM SYS.COLUMNS
WHERE object_id = OBJECT_ID('dbo.TableName')
AND [Name] <> 'ColumnName'
SELECT #sql += ' FROM Dbo.TableName'
EXEC(#sql)
I just wanted to echo #Luann's comment as I use this approach always.
Just right click on the table > Script table as > Select to > New Query window.
You will see the select query. Just take out the column you want to exclude and you have your preferred select query.
There are lot of options available , one of them is :
CREATE TEMPORARY TABLE temp_tb SELECT * FROM orig_tb;
ALTER TABLE temp_tb DROP col_x;
SELECT * FROM temp_tb;
Here the col_x is the column which u dont want to include in select statement.
Take a look at this question : Select all columns except one in MySQL?
You can retrieve the list of column name by simple query and then remove those column by apply where query like this.
SELECT * FROM (
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'TableName'
) AS allColumns
WHERE allColumns.COLUMN_NAME NOT IN ('unwantedCol1', 'unwantedCol2')
If you are using DataGrip you can do the following:
Enter your SELECT statement SELECT * FROM <your_table>;
Put your cursor over * and press Alt+Enter
You will get pop up menu with Expand column list option
Click on it and it will convert * with full list of columns
Now you can remove columns that you don't need
Here is a link for an example on how to do it.
Without creating new table you can do simply (e.g with mysqli):
get all columns
loop through all columns and remove wich you want
make your query
$r = mysqli_query('SELECT column_name FROM information_schema.columns WHERE table_name = table_to_query');
$c = count($r); while($c--) if($r[$c]['column_name'] != 'column_to_remove_from_query') $a[] = $r[$c]['column_name']; else unset($r[$c]);
$r = mysqli_query('SELECT ' . implode(',', $a) . ' FROM table_to_query');
Try the following query:
DECLARE #Temp NVARCHAR(MAX);
DECLARE #SQL NVARCHAR(MAX);
SET #Temp = '';
SELECT #Temp = #Temp + COLUMN_NAME + ', ' FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME ='Person' AND COLUMN_NAME NOT IN ('Id')
SET #SQL = 'SELECT ' + SUBSTRING(#Temp, 0, LEN(#Temp)) +' FROM [Person]';
EXECUTE SP_EXECUTESQL #SQL;
In your case, expand columns of that database in the object explorer. Drag the columns in to the query area.
And then just delete one or two columns which you don't want and then run it. I'm open to any suggestions easier than this.
Only one way to achieve this giving column name. There is no other method found. You must have to list all column name

How can I exclude GUIDs from a select distinct without listing all other columns in a table?

So let's say 'table' has two columns that act as a GUID - the ID column and msrepl_tran_version. Our original programmer did not know that our replication created this column and included it in a comparison, which has resulted in almost 20,000 records being put into this table, of which only 1,588 are ACTUALLY unique, and it's causing long load times.
I'm looking for a way to exclude the ID and replication columns from a select distinct, without having to then list every single column in the table, since I'm going to have to select from the record set multiple times to fix this (there are other tables affected and the query is going to be ridiculous) I don't want to have to deal with my code being messy if I can help it.
Is there a way to accomplish this without listing all of the other columns?
Select distinct {* except ID, msrepl_tran_version} from table
Other than (where COL_1 is ID and COL_N is the replication GUID)
Select distinct COL_2, ..., COL_N-1, COL_N+1, ... from table
After more searching, I found the answer:
SELECT * INTO #temp FROM table
ALTER TABLE #temp DROP COLUMN id
ALTER TABLE #temp DROP COLUMN msrepl_tran_version
SELECT DISTINCT * FROM #temp
This works for what I need. Thanks for the answers guys!
Absolutely, 100% not possible, there is no subtract columns instruction.
It can't be done in the spirit of the OP's initial question. However, it can be done with dynamic sql:
--Dynamically build list of column names.
DECLARE #ColNames NVARCHAR(MAX) = ''
SELECT #ColNames = #ColNames + '[' + c.COLUMN_NAME + '],'
FROM INFORMATION_SCHEMA.COLUMNS c
WHERE c.TABLE_SCHEMA = 'dbo'
AND c.TABLE_NAME = 'YourTable'
--Exclude these.
AND c.COLUMN_NAME NOT IN ('ID', 'msrepl_tran_version')
--Keep original column order for appearance, convenience.
ORDER BY c.ORDINAL_POSITION
--Remove trailing comma.
SET #ColNames = LEFT(#ColNames, LEN(#ColNames) - 1)
--Verify query
PRINT ('SELECT DISTINCT ' + #ColNames + ' FROM [dbo].[YourTable]')
--Uncomment when ready to proceed.
--EXEC ('SELECT DISTINCT ' + #ColNames + ' FROM [dbo].[YourTable]')
One additional note: since you need to select from the record set multiple times and potentially join to other tables, you can use the above to create a view on the table. This should make your code fairly clean.

Avoiding to repeat field names when using INSERT INTO ... SELECT

I have a table with a very large number of fields, and the table is being populated by a INSERT INTO ... SELECT query. Since the number of fields is so large, I get something like this:
INSERT INTO MyTable (
column1,
colunm2,
colunm3,
...
column200)
SELECT column1,
column2,
column3,
...
column200
FROM SomeView;
The above is cumbersome and error prone to maintain, so I'd prefer if it was possible to have some kind of "natural insert" where the field names in the SELECT clause are mapped to the fields with the same names in the target table.
I tried this:
INSERT INTO MyTable
SELECT column1,
column2,
column3,
...
column200
FROM SomeView;
Which is syntactically correct, but relies on matching the order of the fields, which is even more error prone, so what to do? Am I overlooking a much more obvious third option?
Clarification: the purpose is to make it easier to maintain the code in the long run. We will be updating this statement many times, so I am looking for a way to make it more readable and easy to modify.
You can write yourself a query that generates the insert statement (or even executes it at the same time) using dynamic SQL:
DECLARE #cols VARCHAR(MAX)
SELECT #cols =
STUFF( (SELECT ', ' + name
FROM sys.columns
WHERE object_id = object_id('MyTable')
FOR XML PATH('')),1,1,'')
DECLARE #sql VARCHAR(MAX)
SELECT #sql = 'INSERT INTO MyTable (' + #cols + ')
SELECT ' + #cols + ' FROM SomeView'
--print the statement and copy/paste it for saving or using
PRINT (#sql)
--or just execute it right here
EXEC (#sql)
One thing that you can do to speed up the above is to drag the Columns value in SSMS onto a new query and the editor will display all of the column names in a row.
So
INSERT INTO MyTable
SELECT
Drag Columns
FROM SomeView;
Your columns will appear as a comma separated list, some may be missing the [] if needed but it's quicker than typing them.
I came up with this very low tech solution:
INSERT INTO MyTable (column1, colunm2, colunm3, ..., column200)
SELECT column1, column2, column3, ..., column200
FROM SomeView;
It breaks most code formatting guidelines, but at least it is possible to tell how the mapping is done without having to count the fields in two places.

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.
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
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
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:
Then you will get whole select query in New Query Editor Window then remove unwanted column like this:
Done
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);
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
You could create a view that has the columns you wish to select, then you can just select * from the view...
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.
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.
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
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';
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
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.
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;
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)
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?
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.
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');
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
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.
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..
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.
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...
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.
Actually snowflake just released exclude so now you'd just:
SELECT * EXCLUDE [columnA,columnB,...] FROM tableA
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.
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
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;
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
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
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