I'm wondering whether I can use EXISTS (or something similar) in column like this:
SELECT Column1,
Column2,
EXISTS (SELECT 1 FROM Table2 T2 WHERE T2.Column = T1.Column) AS IsFlag
FROM Table1
I know I can do something similar with Count()
SELECT Column1,
Column2,
(SELECT Count(*) FROM Table2 T2 WHERE T2.Column = T1.Column) AS IsFlag
FROM Table1
But that might not be very efficient when Table2 is large
Try this
SELECT Column1,
Column2,
CASE WHEN EXISTS (SELECT 1 FROM Table2 T2
WHERE T2.Column = T1.Column) then 1 ELSE 0 END AS IsFlag
FROM Table1
CASE
WHEN
EXISTS (SELECT 1 FROM Table2 T2 WHERE T2.Column = T1.Column)
THEN 1
ELSE 0
END AS IsFlag
Related
how can I update a column of my table1 with this query?
update table1
set table1.column5 = (
select count(*)
from table2, table1
where table1.column1 = table2.column4
group by table1.column1)
table1 has these columns (column1, column2, column3, column4, column5)
table2 has these columns (column1, column2, column3, column4)
and table2.column4 is foreign key of table1.column1
Use This
UPDATE T1
SET
column5 = COUNT(1)
FROM table2 T2
INNER JOIN table1 T1
ON T1.column1 = T2.column4
GROUP BY T2.column4
Or This
;WITH CNT
AS
(
SELECT
column4,
Cnt = COUNT(1)
FROM table2 T2
GROUP BY T2.column4
)
update t1
SET
column5 = CNT.Cnt
FROM CNT
INNER JOIN table1 T1
ON CNT.column4 = T1.column1
Try this query
with cte as (
select column4, cnt = count(*)
from table2
group by column4
)
update a
a.column5 = b.cnt
from
table1 a
join cte b on a.column1 = b.column4
Any method to do this?
Table1
1
2
3
4
5
Table2
3 (with the condition)
4 (without the condition)
I want to:
Select all records from Table1 if it exists in Table 2, where...(condition)
Select all records from Table1 if it not exists in Table2
Combine both select results. Sort all results with their created date.
For example, the result should be:
Result
1
2
3
5
Hopefully this can help.
SELECT t1.* from table1 t1
JOIN table2 t2
ON t1.ID = t2.ID
UNION ALL
SELECT t1.* from table1 t1 where ID in
(
SELECT t2.ID from table1 t1 except Select t2.ID from table2 t2
)
ORDER BY t1.CreatedDate
You can achieve this by doing:
SELECT t1.id
FROM Table1 t1
LEFT JOIN Table2 t2 on t1.id = t2.id
WHERE condition OR t2.id IS NULL
ORDER BY t1.CreatedDate;
See fiddle (I assumed condition to be t2.id!=4, but it can be anything else depending on other data in your tables).
There could be multiple solution.
One way
we can get the result set using two different queries and at last combine both of the result-set using UNION
Another way,
First statement is saying that get all the result set from TABLE1 if it exists in TABLE2 as well with some criteria (condition in where clause)
means using INNER JOIN we can achieve this
Second statement is saying get all the result set from TABLE1 which are not present in TABLE2
means along with INNER JOIN ed query also include the TABLE1's data if not present in TABLE2
here we can take the help of LEFT OUTER JOIN (taking TABLE1 on the left side)
Assumption: (condition: t1.Id != 4)
Let's try to understand the query using both of the above mentioned ways
---- -- --Step1 Create table and insert records
---- create table1 with Id int identity columsn
--CREATE TABLE Table1 (Id INT IDENTITY(1,1), CreatedDate smalldatetime default(getdate()));
--go
---- insert 1st 5 integers into Table1
--INSERT INTO Table1 DEFAULT VALUES
--go 5
---- create Table2 with Id int column
--CREATE TABLE Table2 (Id INT , CreatedDate smalldatetime default(getdate()));
--go
---- insert records 3,5 into Table2
--INSERT INTO Table2(Id) VALUES (3), (4);
-- -- -- Solution: one way
; WITH cteMyFirstResult AS
(
-- 2.1. Select all records from Table1 if it exists in Table 2, where...(condition)
SELECT
Id, CreatedDate
FROM Table1 AS t1
WHERE t1.Id IN (SELECT Id FROM Table2 AS t2)
AND t1.Id != 4 -- assumption it can be any condition
),cteMySecondResult AS (
-- 2.2. Select all records from Table1 if it not exists in Table2
SELECT
Id, CreatedDate
FROM Table1 AS t1 WHERE t1.Id NOT IN (SELECT Id FROM Table2 AS t2)
)
-- 2.3. Combine both select results. Sort all results with their created date.
SELECT
Id, CreatedDate
FROM cteMyFirstResult
UNION
SELECT
Id, CreatedDate
FROM cteMySecondResult
ORDER BY CreatedDate;
-- -- Solution: Another way (with bug)
SELECT t1.Id, t1.CreatedDate
FROM Table1 AS t1
LEFT JOIN Table2 AS t2 on t1.id = t2.id
WHERE t1.Id != 4
Order by T1.CreatedDate;
-- in this query we are using the criteria after doing the join operation.
-- thus after filtering out the result set based on JOIN Condition this condition will get applied
-- and if there is any null record in the Table1 for column Id (used in join) will not come in the final result-set
-- to avoid this we can include NULL check along with our criteria
-- -- Solution: Another way
SELECT t1.Id, t1.CreatedDate
FROM Table1 AS t1
LEFT JOIN Table2 AS t2 on t1.id = t2.id
WHERE ( t1.Id != 4 ) OR t1.Id IS NULL -- include all your criteria within small-barcket)
Order by T1.CreatedDate;
Thanks for all responses.
I come out with the answer I want:
SELECT *
FROM Table1 t1
WHERE NOT EXISTS(SELECT 1 FROM Table2 t2
WHERE t1.ID = t2.ID
AND t2.CIF_KEY = #CifKey
AND t2.STATUS <> ''3'')
AND (condition in where clause)
I have an sql query like this
Select col1, (select abc from table2 where def=1) as col2
From Table1 inner join table3 on Table1.id = table3.id
Where col2 = 4
The problem is that the where condition doesn't work. I get an error saying
Invalid column name 'col2'
Kindly help me fix this sql query.
Thanks in advance
You can define it in a CROSS APPLY and then reference in the SELECT and WHERE
SELECT col1,
col2
FROM Table1
INNER JOIN table3
ON Table1.id = table3.id
CROSS APPLY (SELECT abc
FROM table2
WHERE def = 1) C(col2)
WHERE col2 = 4
Using a CTE (Common Table Expression):
WITH SubQuery AS (Col2) {
SELECT
ABC
FROM
table2
WHERE
def = 1
}
SELECT
T.Col1,
S.Col2
FROM
SubQuery S,
Table1 T
INNER JOIN table3 t3
ON T.id = t3.id
WHERE
S.Col2 = 4
Although I must say I agree with the first comment - this makes no sense since your subquery is not correlated (joined) to the rest of your query...
I need to build an SQL statement to delete from certain table the records that match another select statement.
In Teradata we use
delete from table1
where (col1, col2) in (
select col1,col2
from table2
)
While in SQL Server it's not allowed to have more than 1 column in the WHERE..IN clause. I thought I can use the WITH clause:
with tempTable(col1,col2) as (
select col1,col2
from table2
)
delete from table1
where table1.col1 = tempTable.col1
and table1.col2 = tempTable.col2
How to use WITH..DELETE clause? Is there another way?
This should do it:
DELETE Table1
from Table1 t1
inner join tempTable t2
on t2.Col1 = t1.Col1
and t2.Col2 = t1.Col2
First build a query that selects the rows you need:
SELECT t1.*
FROM [Table1] t1
INNER JOIN [Table2] t2 ON t1.[col1] = t2.[col1] AND t1.[Col2]=t2.[Col2]
Test it to make sure it returns exactly the rows you want to delete. Then turn it into a delete statement by changing the "SELECT" to "DELETE" and removing the column list:
DELETE t1
FROM [Table1] t1
INNER JOIN [Table2] t2 ON t1.[col1] = t2.[col1] AND t1.[Col
delete from table1 t1 where exists
(
select 1 from table2 t2 where t1.col1 = t2.col1 and t1.col2 > t2.col2
)
with tempTable(col1,col2) as (
select col1,col2
from table2
)
delete table1 from tempTable
where table1.col1 = tempTable.col1
and table1.col2 = tempTable.col2
This works for me
WITH CTE AS
(
SELECT TOP 50000 *
from v020101hist order by data
)
DELETE FROM CTE
I need to fetch a column from table2, if row exists, if not return it as null.
If i use ,case when it fetches only matched rows between table1 and table2.
If i use left outer join it fetches all the rows from table1 even though
condition table1.code='A'
So i need ,some thing like this.
select table1.id,
if(row exist in table2 for query(table2.relation_type_id=55 and table1.id=table2.related_id)
then
return table2.parent_id
else
null
as parent_id,
table1.description,
from table1,table2 where table1.code='A'
SELECT table1.id, table2.parent_id as parent_id
FROM table1
LEFT OUTER JOIN table2 ON (table1.id = table2.related_id)
WHERE table1.code = 'A';
EDIT based on comment :
SELECT table1.id, sub.parent_id as parent_id
FROM table1
LEFT OUTER JOIN (select parent_id,related_id from table2 where relation_type_id =55) sub ON (table1.id = sub.related_id)
WHERE table1.code = 'A';
Have you tried a sub-query?
select table1.id,
(select table2.parent_id from table2 where table2.relation_type_id=55 and table2.related_id=table1.id) parent_id,
table1.description,
from table1 where table1.code='A'