I have a query and I want to check if the output has at least one row, if not , show some message like "No data". I have tried like described here : https://cloud.google.com/bigquery/docs/reference/standard-sql/scripting#if
WITH
cte1 AS (
SELECT id, name
FROM My_table
)
SELECT
* from cte1;
IF (SELECT COUNT(*) = 0 FROM cte1) THEN SELECT "No data"; END IF
You can do something like this:
WITH cte1 AS (
SELECT id, name
FROM My_table
)
SELECT id, name
FROM cte1;
UNION ALL
SELECT NULL, 'No Data'
FROM (SELECT 1 as x) x
WHERE NOT EXISTS (SELECT 1 FROM cte2);
Note: The subqueries need to return the same columns.
Related
i need help on HAVING COUNT , i have a result set of data below:
CREATE TABLE #tmpTest1 (Code VARCHAR(50), Name VARCHAR(100))
INSERT INTO [#tmpTest1]
(
[Code],
[Name]
)
SELECT '160215-039','ROBIN'
UNION ALL SELECT '160215-039','ROBIN'
UNION ALL SELECT '160215-046','SENGAROB'
UNION ALL SELECT '160215-046','BABYPANGET'
UNION ALL SELECT '160215-045','JONG'
UNION ALL SELECT '160215-045','JAPZ'
UNION ALL SELECT '160215-044','AGNES'
UNION ALL SELECT '160215-044','AGNES'
UNION ALL SELECT '160215-041','BABYTOT'
UNION ALL SELECT '160215-041','BABYTOT'
UNION ALL SELECT '160215-041','BABYTOT'
i want to show only the rows that have the same code but different name , so in this case my expected result is below since those are have the same code but different name:
160215-045 JAPZ
160215-045 JONG
160215-046 BABYPANGET
160215-046 SENGAROB
but when i try to group the two columns then use the having count, below is my query:
SELECT [Code], [Name] FROM [#tmpTest1]
GROUP BY [Code], [Name] HAVING COUNT([Code]) > 1
It gives me wrong result below which have the rows that have the same code and name, it is the opposite of what i want.
160215-044 AGNES
160215-041 BABYTOT
160215-039 ROBIN
How can i get my expected output ?
Thanks in advance, any help would much appreciated.
I believe this query will give you the result you want, although your original question is a bit unclear.
SELECT t1.[Code], t1.[Name]
FROM [#tmpTest1] t1
INNER JOIN
(
SELECT [Code]
FROM [#tmpTest1]
GROUP BY [Code]
HAVING COUNT(DISTINCT [Name]) > 1
) t2
ON t1.[Code] = t2.[Code]
Follow the link below for a running demo:
SQLFiddle
If you want rows with the same code and name, then use window functions:
select t.*
from (select t.*, count(*) over (partition by code, name) as cnt
from #temptest1 t
) t
where cnt >= 2;
From your comment
if there is 1 different name for the codes , i want to show those
records for me to know that there is one differs to others..
This sounds like an exists query because you want to check if another row with the same code but different name exists.
select * from [#tmpTest1] t1
where exists (
select 1 from [#tmpTest] t2
where t2.code = t1.code
and t2.name <> t1.name
)
I have different simple SQL request that return only one value. Example
SELECT COUNT(*) FROM Person
OR
SELECT COUNT(*) FROM Category
I would to get all these infos in a unique request, with a column by request...
I tried something like that but it doesn't work :
SELECT COUNT(C.CategoryId) As nbPeople, COUNT(P.PersonID) As nbCategories FROM Category C, Person P
This works but I get only one column, and a row by request
SELECT COUNT(*) FROM Person UNION SELECT COUNT(*) FROM Category
How Can I simply do that ?
Thanks
When using SQL Server, you can try this:
SELECT ( select COUNT(C.CategoryId)
from Category C
) As nbPeople
, ( select COUNT(P.PersonID)
from Person P
) As nbCategories
In Oracle for example, you need to add this at the bottom
FROM dual
You can use UNION ALL like following:
SELECT '' AS [StatisticName], 1 AS [StatisticCount]
WHERE 1=0
UNION ALL
SELECT 'PersonCount', COUNT(*) FROM [Person]
UNION ALL
SELECT 'CathegoryCount', COUNT(*) FROM [Category]
First select with WHERE 1=0 is for create column header names only and is not necessary.
Try this.
select * from
(select count(*) cnt1
from Table1) t1
join
(select count(*) as cnt2
from Table2) t2 on 1=1
I want to do the following query, how can I implement it?
SELECT * FROM table WHERE routeNum LIKE 'N10%'
-->if no rows return, WHERE clause change to routeName LIKE '&something%'
I think this will work for you:
WITH CTE AS (
SELECT 2 AS 'INDEX', * FROM table WHERE routeNum LIKE 'N10%'
UNION ALL
SELECT 1 AS 'INDEX', * FROM table WHERE routeNum LIKE '&something%'
)
SELECT *
FROM CTE
WHERE CTE.INDEX = (SELECT MAX(INDEX) FROM CTE)
As you have to choose between two result sets, you will need two queries, which will return two different sets and then, based on the 'index' which corresponds to the query that has run, you choose how to display your results.
Here is a SQLFiddle demo.
A possible solution
WITH cte AS
(
SELECT *
FROM routes
WHERE routeNum LIKE 'N10%'
)
SELECT * FROM cte
UNION ALL
SELECT * FROM routes
WHERE routeNum LIKE 'something else%'
AND NOT EXISTS
(
SELECT *
FROM cte
)
Here is SQLFiddle demo
WITH tmp AS
(
SELECT t.*,
CASE
WHEN routeNum LIKE 'N10%' THEN 1
WHEN routeNum LIKE '&something%' THEN 2
ELSE 3 END AS q
FROM table t
)
SELECT * FROM tmp t
WHERE q = CASE WHEN (SELECT COUNT(*) FROM tmp WHERE q = 1 ) > 0 THEN 1 ELSE 2 END
I have the following table structure:
Id, Message
1, John Doe
2, Jane Smith
3, Error
4, Jane Smith
Is there a way to get the error record and the surrounding records? i.e. find all Errors and the record before and after them.
;WITH numberedlogtable AS
(
SELECT Id,Message,
ROW_NUMBER() OVER (ORDER BY ID) AS RN
FROM logtable
)
SELECT Id,Message
FROM numberedlogtable
WHERE RN IN (SELECT RN+i
FROM numberedlogtable
CROSS JOIN (SELECT -1 AS i UNION ALL SELECT 0 UNION ALL SELECT 1) n
WHERE Message='Error')
WITH err AS
(
SELECT TOP 1 *
FROM log
WHERE message = 'Error'
ORDER BY
id
),
p AS
(
SELECT TOP 1 l.*
FROM log
WHERE id <
(
SELECT id
FROM err
)
ORDER BY
id DESC
)
SELECT TOP 3 *
FROM log
WHERE id >
(
SELECT id
FROM p
)
ORDER BY
id
Adapt this routine to pick out your target.
DECLARE #TargetId int
SET #TargetId = 3
select *
from LogTable
where Id in (-- "before"
select max(Id)
from LogTable
where Id < #TargetId
-- target
union all select #TargetId
-- "after"
union all select min(Id)
from LogTable
where Id > #TargetId)
select id,messag from
(Select (Row_Number() over (order by ID)) as RNO, * from #Temp) as A,
(select SubRNO-1 as A,
SubRNO as B,
SubRNO+1 as C
from (Select (Row_Number() over (order by ID)) as SubRNO, * from #Temp) as C
where messag = 'Error') as B
where A.RNO = B.A or A.RNO = B.B or A.RNO = B.C
;WITH Logs AS
(
SELECT ROW_NUMBER() OVER (ORDER BY id), id, message as rownum FROM LogTable lt
)
SELECT curr.id, prev.id, next.id
FROM Logs curr
LEFT OUTER JOIN Logs prev ON curr.rownum+1=prev.rownum
RIGHT OUTER JOIN Logs next ON curr.rownum-1=next.rownum
WHERE curr.message = 'Error'
select id, message from tbl where id in (
select id from tbl where message = "error"
union
select id-1 from tbl where message = "error"
union
select id+1 from tbl where message = "error"
)
Get fixed number of rows before & after target
Using UNION for a simple, high performance query (I found selected answer WITH query above to be extremely slow)
Here is a high performance alternative to the WITH top selected answer, when you know an ID or specific identifier for a given record, and you want to select a fixed number of records BEFORE and AFTER that record. Requires a number field for ID, or something like date that can be sorted ascending / descending.
Example: You want to select the 10 records before and after a specific error was recorded, you know the error ID, and can sort by date or ID.
The following query gets (inclusive) the 1 result above, the identified record itself, and the 1 record below. After the UNION, the results are sorted again in descending order.
SELECT q.*
FROM(
SELECT TOP 2
id, content
FROM
the_table
WHERE
id >= [ID]
ORDER BY id ASC
UNION
SELECT TOP 1
id, content
FROM
the_table
WHERE
id < [ID]
ORDER BY id DESC
) q
ORDER BY q.id DESC
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