I have a table with columns 'Id' and 'Status'.
I want to write a SQL statement to select top 50 rows from this table with 25 rows with Status 1 and 25 rows with Status 2 in one SQL query.
I want my result to have rows with alternate status.
Please suggest me how to write this Query.
If you use MSSQL you can do this:
SELECT TOP 25
*
FROM
Table1
WHERE
Table1.Status=1
UNION ALL
SELECT TOP 25
*
FROM
Table1
WHERE
Table1.Status=2
If you use MYSQL you have to use LIMIT. Like this:
(
SELECT
*
FROM
Table1
WHERE
Table1.Status=1
LIMIT 25
)
UNION ALL
(
SELECT
*
FROM
Table1
WHERE
Table1.Status=2
LIMIT 25
);
For SQL Server, use TOP:
SELECT TOP 25 * FROM TableName WHERE Status=1
UNION ALL
SELECT TOP 25 * FROM TableName WHERE Status=2
For alternative result:
SELECT * FROM
(
SELECT TOP 25 *,ROW_NUMBER() OVER(ORDER BY Status) as RN FROM TableName WHERE Status=1
UNION ALL
SELECT TOP 25 *,ROW_NUMBER() OVER(ORDER BY Status) as RN FROM TableName WHERE Status=2
) T
ORDER BY RN
Related
I need to have one query for to select all records of KitchenBlinkSound='Y' plus top 1 of KitchenBlinkSound='N', here is my table structure.
And my requested result will be OrderNo 225,226,227. Basically it contains all KitchenBlinkSound='Y' records plus top 1 of KitchenBlinkSound='N' record.
SELECT * FROM TABLE WHERE KitchenBlinkSound='Y'
UNION ALL
SELECT TOP 1 * FROM TABLE WHERE KitchenBlinkSound='N'
ORDER BY ORDERNO
UPDATE
SELECT TOP 3 * FROM
(
SELECT * FROM #TABLE1 WHERE KitchenBlinkSound='Y'
UNION ALL
SELECT ORDERNO,KITCHENSTATUS,KitchenBlinkSound FROM
(
SELECT *,
ROW_NUMBER() OVER(PARTITION BY KitchenBlinkSound ORDER BY ORDERNO ASC) RNO
FROM #TABLE1 WHERE KitchenBlinkSound='N'
)TAB
WHERE TAB.RNO=1
)MAIN
As sub-queries doesn't allow ORDER BY, ROW_NUMBER() is added in order to make sure that you are selecting the TOP 1 ORDERNO in ascending order. If you want to take in descending order change ASC to DESC.
Select * from [your table name] where KitchenBlickSound = 'Y'
UNION
Select TOP 1 * from [your table name] where KitchenBlickSound = 'N'
I want to write a query like
select top 10 * from A
order by price
union
select top 3 * from A
order by price
or sth like that
select top 10 * from A
where name like '%smt%'
order by price
union
select top 3 * from A
where name not like '%smt%'
order by price
Can you please help me?
This should work:
SELECT *
FROM (SELECT TOP 10 A.*, 0 AS Ordinal
FROM A
ORDER BY [Price]) AS A1
UNION ALL
SELECT *
FROM (SELECT TOP 3 A.*, 1 AS Ordinal
FROM A
ORDER BY [Name]) AS A2
ORDER BY Ordinal
From MSDN:
In a query that uses UNION, EXCEPT, or INTERSECT operators, ORDER BY
is allowed only at the end of the statement. This restriction applies
only to when you specify UNION, EXCEPT and INTERSECT in a top-level
query and not in a subquery.
Edited: to force the order you need to apply an ORDER BY to the outer query. I've added a constant value column to both queries.
This is a real hacky way to do this. You probably want these as separate queries in reality, but this should give you the result you want...
select *
from (
select top 10 *, 1 as 'ord', price as 'ordprice' from A
union
select top 3 *, 2 as 'ord', 0 as 'ordprice' from A
) a
order by ord, ordprice, name
UNION doesn't like ORDER by clauses in the UNIONed expressions.
Try this:
SELECT * FROM
(SELECT TOP 10 * FROM A ORDER BY Price) SetA
UNION
SELECT * FROM
(SELECT TOP 3 * FROM a ORDER BY name) Setb
[ORDER BY something]
This spoofs the UNION operator into ignoring the ORDER BYs, which still operate correctly on the TOP operator.
You can apply a final ORDER BY to order the UNIONed set, if you like.
[No longer applies exactly to your question now that it's edited!]
select top 10 *,0 as RS from A
union
select top 3 *,1 as RS from A
order by
RS,
CASE WHEN RS=0 THEN price END, --Don't affect RS 1
name
cmd.CommandText = "SELECT 0 AS Employee_ID, 'No Employees' as Employee_FullName , 'id1' Orderkey
UNION ALL
SELECT Employee_ID, Employee_FullName, 'id2' Orderkey
FROM tblEmployee
ORDER BY Orderkey, Employee_FullName"
ds = dbconn.SelectQuery(cmd)
ds.Tables(0).Columns.Remove(ds.Tables(0).Columns("Orderkey"))
How to select top 2 , bottom 2 and 6 random (not in Top 2 and Bottom 2) records of the table using one SQL select query?
In MS SQL 2005/2008:
with cte
as
(
select
row_number() over (order by name) RowNumber,
row_number() over (order by newid()) RandomOrder,
count(*) over() Total,
*
from sys.tables
)
select *
from cte
where RowNumber <= 2 or Total - RowNumber + 1 <= 2
union all
select *
from
(
select top 6 *
from cte
where RowNumber > 2 and Total - RowNumber > 2
order by RandomOrder
) tt
Replace sys.tables with your table name and alter order by name to specify order condition for top 2 and bottom 2.
Perhaps not a single select statment, but it can be executed in one call:
/* Top 2 - change order by to get the 'proper' top 2 */
SELECT * from table ORDER BY id DESC LIMIT 2
UNION ALL
/* Random 6.. You may want to add a WHERE and random data to get the random 6 */
/* Old Statement before edit - SELECT * from table LIMIT 6 */
SELECT * from table t
LEFT JOIN (SELECT * from table ORDER BY id DESC LIMIT 2) AS top ON top.id = t.id
LEFT JOIN (SELECT * from table ORDER BY id DESC LIMIT 2) AS bottom ON bottom.id = t.id
WHERE ISNULL(top.id ) AND ISNULL(bottom.id)
ORDER BY RANDOM()
LIMIT 6
UNION ALL
/* Bottom 2 - change order by to get the 'proper' bottom 2 */
SELECT * from table ORDER BY id ASC LIMIT 2
Something along those lines. Basically the UNION All is the trick.
Assuming the "order" is by the id column:
select * from (select id, id from my_table order by id limit 2) t1
union
select * from (select id, id from my_table where id not in (
select * from (select id from my_table order by id asc limit 2) t22
union
select * from (select id from my_table order by id desc limit 2 ) t23)
order by rand()
limit 6) t2
union
select * from (select id, id from my_table order by id desc limit 2) t3
EDIT: Fixed syntax and tested query - it works
I want Union of two queries with the first query resultset getting the first ten rownums in Oracle.
Example:
Like if first query has 10 rows and max rownum is 10.I want second query rownum to be started from 11 in the result of union.
SELECT *
FROM (
SELECT *
FROM table1
ORDER BY
col1
)
WHERE rownum <= 10
UNION ALL
SELECT *
FROM (
SELECT *, rownum AS rn
FROM (
SELECT *
FROM table2
ORDER BY
col2
)
)
WHERE rn > 10
In Microsoft SQL Server 2005 or above, I would like to get the first row, and if there is no matching row, then return a row with default values.
SELECT TOP 1 ID,Name
FROM TableName
UNION ALL
SELECT 0,''
ORDER BY ID DESC
This works, except that it returns two rows if there is data in the table, and 1 row if not.
I'd like it to always return 1 row.
I think it has something to do with EXISTS, but I'm not sure.
It would be something like:
SELECT TOP 1 * FROM Contact
WHERE EXISTS(select * from contact)
But if not EXISTS, then SELECT 0,''
What happens when the table is very full and you might want to specify which row of your top 1 to get, such as the first name? OMG Ponies' query will return the wrong answer in that case if you just change the ORDER BY clause. His query also costs about 8% more CPU than this modification (though it has equal reads)
SELECT TOP 1 *
FROM (
SELECT TOP 1 ID,Name
FROM TableName
ORDER BY Name
UNION ALL
SELECT 0,''
) X
ORDER BY ID DESC
The difference is that the inner query has a TOP 1 also, and which TOP 1 can be specified there (as shown).
Just for fun, this is another way to do it which performs very closely to the above query (-15ms to +30ms). While it's more complicated than necessary for such a simple query, it demonstrates a technique that I don't see other SQL folks using very often.
SELECT
ID = Coalesce(T.ID, 0),
Name = Coalesce(T.Name, '')
FROM
(SELECT 1) X (Num)
LEFT JOIN (
SELECT TOP 1 ID, Name
FROM TableName
ORDER BY ID DESC
) T ON 1 = 1 -- effective cross join but does not limit rows in the first table
Use:
SELECT TOP 1
x.id,
x.name
FROM (SELECT t.id,
t.name
FROM TABLENAME t
UNION ALL
SELECT 0,
'') x
ORDER BY id DESC
Using a CTE equivalent:
WITH query AS (
SELECT t.id,
t.name
FROM TABLENAME t
UNION ALL
SELECT 0,
'')
SELECT TOP 1
x.id,
x.name
FROM query x
ORDER BY x.id DESC
CREATE TABLE #sample(id INT, data VARCHAR(10))
SELECT TOP 1 id, data INTO #temp FROM #sample
IF ##ROWCOUNT = 0 INSERT INTO #temp VALUES (null, null)
SELECT * FROM #temp
put the top oustide of the UNION query
SELECT TOP 1 * FROM(
SELECT ID,Name
FROM TableName
UNION ALL
SELECT 0,''
) z
ORDER BY ID DESC
IF EXISTS ( SELECT TOP 1 ID, Name FROM TableName )
BEGIN
SELECT TOP 1 ID, Name FROM TableName
END
ELSE
BEGIN
--exists returned no rows
--send a default row
SELECT 0, ''
END