Delete the 'first' record from a table in SQL Server, without a WHERE condition
Is it possible to delete the ‘first’ record from a table in
SQL Server, without using any
WHERE condition and without using a cursor?
8 Solutions collect form web for “Delete the 'first' record from a table in SQL Server, without a WHERE condition”
WITH q AS ( SELECT TOP 1 * FROM mytable /* You may want to add ORDER BY here */ ) DELETE FROM q
DELETE TOP (1) FROM mytable
will also work, but, as stated in the documentation:
The rows referenced in the
TOPexpression used with
DELETEare not arranged in any order.
Therefore, it’s better to use
WITH and an
ORDER BY clause, which will let you specify more exactly which row you consider to be the first.
depends on your DBMS (people don’t seem to know what that is nowadays)
-- MYSql: DELETE FROM table LIMIT 1; -- Postgres: DELETE FROM table LIMIT 1; -- MSSql: DELETE TOP(1) FROM table; -- Oracle: DELETE FROM table WHERE ROWNUM = 1;
No, AFAIK, it’s not possible to do it portably.
There’s no defined “first” record anyway – on different SQL engines it’s perfectly possible that “
SELECT * FROM table” might return the results in a different order each time.
Define “First”? If the table has a PK then it will be ordered by that, and you can delete by that:
DECLARE @TABLE TABLE ( ID INT IDENTITY(1,1) NOT NULL PRIMARY KEY, Data NVARCHAR(50) NOT NULL ) INSERT INTO @TABLE(Data) SELECT 'Hello' UNION SELECT 'World' SET ROWCOUNT 1 DELETE FROM @TABLE SET ROWCOUNT 0 SELECT * FROM @TABLE
If the table has no PK, then ordering won’t be guaranteed…
Does this really make sense?
There is no “first” record in a relational database, you can only delete one random record.
What do you mean by «’first’ record from a table» ? There’s no such concept as “first record” in a relational db, i think.
Using MS SQL Server 2005, if you intend to delete the “top record” (the first one that is presented when you do a simple “*select * from tablename*”), you may use “delete top(1) from tablename“… but be aware that this does not assure which row is deleted from the recordset, as it just removes the first row that would be presented if you run the command “select top(1) from tablename“.
Similar to the selected answer, a table source can be used, in this case a derived query:
delete from dd from ( select top 1 * from my_table ) dd
Feel free to add orderbys and conditions.
For the next example, I’ll assume that the restriction on ‘where’ is due to not wanting to select a row based on its values. So assuming that we want to delete a row based on position (in this case the first position):
delete from dd from ( select *, row = row_number() over (order by (select 1)) from my_table ) dd where row = 1
Note that the (select 1) makes it the sort order that the tables or indexes are in. You can replace that with a newid to get fairly random rows.
You can also add a partition by to delete the top row of each color, for example.
DELETE Field FROM Table WHERE Field IN (SELECT TOP 1 Field FROM Table ORDER BY Field DESC)