I two tables, one table contains the names of columns, the other table contains the actual data that I need to display in a report. The data and columns are linked by a column key.
Is there a way to build a select statement that can use the column name from the column table for the actual temp table column?
Something like this;
Select A.value AS B.ColumnName
Simply put Can I create a table column name based on the value in another table in sql?
You can´t do it without using dynamic SQL as mentioned question that can be useful for you.
SQL Server: How to set column alias from another table during select?
Related
I have got two tables, Table A containing my subject that needs to be updated and Table B that contains XML used to populate the columns in Table A.
A new column has been added to Table A which relates to a specific piece of in the XML.
Any ideas how I can query the XML and insert the into the new column?
UPDATE:
I have tried to query the XML using
select
xml
from
TableB
where
xml.value('(/path/value)[1]','string') like 'VALUE'
However when I do this, "xml.value" is highlghted as an error "Cannot find either column "xml" or the user-defined function or aggregate "xml.value", or the name in ambiguous"
I am stuck with this question. I know table can be created with the select statement.
CREATE TABLE new_orders (ordr_id,order_date DEFAULT SYSDATE,cus_id)
AS
Select order_id.order_date,customer_id FROM Orders;
Which statement would be true regarding the above question ?
The NEW_ORDERS table would not get created beacuse the default value cannot be specified in the column definition.
The NEW_ORDERS table would get created and only the NOT NULL constraint define on the specified columnns would be passed to the new table.
The NEW_ORDERS table would not get created because the column names in the CREATE TABLE command and the SELECT clause do not match.
The NEW_ORDERS table would get created and all the constraints defined on the specified columns in the orders table would be passed to new Table.
I think correct answer should be 3, but it's wrong. The correct answer according to my book is 2. I don't get it how?
The answer should not be 3. Because in the select statement, you are taking values from Orders table. So you will use the column names of that table. Selecting value from there, you are inserting it into new_orders. So, the column names don't have to be same because they are different tables.
I want to copy the content of one column in table A and replace the contents (not insert into it - the number of rows will be the same) of another column in another table.
I can't a where condition, the table has only just been created at this point with one empty timestamp column. it will be populated via pyodbc class after the timestamps have been added - this query will fill the timestamps for me
What is the SQL command for this?
Thanks!
After discussion, this is the query needed : INSERT INTO OCAT_test_table (DateTimeStamp) SELECT DateTimeStamp FROM DunbarGen
I have a "source data" table with columns A,B,C,D,E,F
I use this table to populate a live table by using
INSERT INTO LIVETABLE
SELECT *
FROM SOURCEDATATABLE
Recently, a new column (C1) was added to the LIVETABLE
All I want to do is insert a C1 column into my SOURCEDATATABLE between C and D so that it now is A,B,C,C1,D,E,F. There is no need to populate with data as the LIVETABLE accepts NULLs
Is there any easy solution?
EDIT - MISSING INFORMATION
This table is one of many and my approach to using the INSERT INTO is due to having to use dynamic SQL (for various other reasons) so I cannot specify the column names
There is a reason for the Mantra "I shall not use SELECT *" and you ran straight into it. Add the column to SOURCEDATATABLE (if necessary) and enumerate the columns in the SELECT clause using NULL for the new one.
The only way to insert a new column between two columns is to create a new table with the columns in the order you want, copy the data into it, drop the old table and rename the new table with the old name. Make sure you remove primary key identities to maintain the identity column.
I have a sql table that I am trying to add a column from another table to. Only when I execute the alter table query it does not pull the values out of the table to match the column where I am trying to make the connection.
For example I have column A from table 1 and column A from table 2, they are supposed to coincide. ColumnATable1 being an identification number and ColumnATable2 being the description.
I tried this but got an error...
alter table dbo.CommittedTbl
add V_VendorName nvarchar(200)
where v_venkey = v_vendorno
It tells me that I have incorrect syntax... Anyone know how to accomplish this?
alter table dbo.CommittedTbl
add V_VendorName nvarchar(200);
go
update c
set c.V_VendorName = a.V_VendorName
from CommittedTbl c
join TableA a
on c.v_venkey = a.v_vendorno;
go
I'm just guessing at your structure here.
alter table 2 add column A <some_type>;
update table2 set column A = (select column_A from table2 where v_venkey = v_vendorno);
Your names for tables and columns are a bit confusing but I think that should do it.
There is no WHERE clause for an ALTER TABLE statement. You will need to add the column (your first two lines), and then insert rows based upon a relationship you define between the two tables.
ALTER TABLE syntax:
http://msdn.microsoft.com/en-us/library/ms190273%28v=sql.90%29.aspx
There are several languages within SQL:
DDL: Data Definition Language - this defines the schema (the structure of tables, columns, data types) - adding a column to a table affects the table definitions and all rows will have that new column (not just some rows according to a criteria)
DML: Data Manipulation Language - this affects data within a table, and inserting, updating or other changes fall into this and you can update some data according to criteria (and this is where a WHERE clause would come in)
ALTER is a DDL statement, while INSERT and UPDATE are DML statements.
The two cannot really be mixed as you are doing.
You should ALTER your table to add the column, then INSERT or UPDATE the column to include appropriate data.
Is it possible that you want a JOIN query instead? If you want to join two tables or parts of two tables you should use JOIN.
have a look at this for a start if you need to know more LINK
hope that helps!