I have table with columns say:
col1, col2, col3
I want to find if either values say 22 or 33 or 3 is/are in the columns.
For single value assume 22, I could have done:
SELECT * from table_name
WHERE 22 IN (col1, col2, col3)
How can I find 22, 33 in columns col1, col2, col3.
Any help is highly appreciable.
Thanks!
SELECT * from table_name
WHERE col1 IN (1,2,3) or
col2 IN (1,2,3) or
col3 IN (1,2,3)
Maybe also like this
with search as
(
select 1 v
union all
select 2 v
union all
select 3 v
)
select distinct t.*
from table_name t
join search s on t.col1 = s.v or t.col2 = s.v or t.col3 = s.v
dbfiddle demo
Related
I am using this query to get duplicate rows in sql
SELECT
col1, col2, COUNT(*)
FROM
emp
GROUP BY
col1, col2
HAVING
COUNT(*) > 1
I have used col1, col2 here to match duplicates but what if I have 1000 more columns will I write all of there names? Like :
SELECT
col1, col2,...,col1000 COUNT(*)
FROM
emp
GROUP BY
col1, col2...,col1000
HAVING
COUNT(*) > 1
Or is there any better way?
I have 22 tables where each has many columns. I want to select 10 columns conditioning on 4 column values using WHERE. For this, I have to repeat these 4 conditions and 10 columns for all 22 tables, which is inconvenient. Is there a more efficient way to do this?
If the 22 tables have the same structure and the conditions on 4 columns are equal or similar, you can union tables in a subquery and put only one where externally.
Example:
select x.*
from
(
select col1, col2, col3, col4
from tab1
union all
select col1, col2, col3, col4
from tab2
union all
select col1, col2, col3, col4
from tab3
) x
where x.col1 = 'value'
and x.col2 = 'other value'
How do I structure my query so I can count how many occurrences of a value in column 1 appears in column 2 and then store that result in a new column in the same table? (If a value is duplicated in the first column I still want to store the same value in the new column) For example if I had a table like this:
COL1 COL2
1 2
1 4
2 1
3 1
4 1
4 2
The resulting table will look like this:
COL1 COL2 COL3
1 2 3
1 4 3
2 1 2
3 1 0
4 1 1
4 2 1
Any help is appreciated I am new to sql! Thanks in advance!
Select
col1,
col2,
COALESCE(col3,0) as col3
FROM
mytable
LEFT JOIN
( Select count(*) as col3, col2
from mytable
GROUP BY col2) as temp ON temp.col2 = mytable.col1
And if you want the update (thanks Thorsten Kettner ) :
UPDATE mytable
LEFT JOIN ( Select count(*) as col3, col2
from mytable
GROUP BY col2) as temp ON temp.col2 = mytable.col1
SET mytable.col3 = COALESCE(temp.col3,0)
You can easily count on-the-fly. Don't store this redundantly. This would only cause problems later.
select
col1,
col2,
(
select count(*)
from mytable match
where match.col2 = mytable.col1
) as col3
from mytable;
If you think you must do it; here is the according UPDATE statement:
update mytable
set col3 =
(
select count(*)
from mytable match
where match.col2 = mytable.col1
);
To do that, you can try :
SELECT COL1, COL2, (SELECT COUNT(COL1) FROM `tablename` AS t2
WHERE t2.COL1 = t1.COL1) AS COL3 FROM `tablename` AS t1
Enjoy :)
CREATE TABLE tmp ( col1 int, col2 int );
INSERT INTO tmp VALUES (1,3), (2,5), (3,7);
SELECT col1, col2, SUM(col2) AS Total FROM tmp; -- ???
The SELECT statement leaves me with this data set:
col1 col2 Total
1 3 15
Is there a way to allow all the rows to appear without introducing a subquery, so that the result is this:
col1 col2 Total
1 3 15
2 5 15
3 7 15
You can use a cross join to avoid a subquery:
SELECT t1.col1, t1.col2, sum(t2.col2) sum_col2
from tmp t1
cross join tmp t2
group by 1, 2
See SQL fiddle
Note that this only works if combinations of col1 and col2 are unique.
I have a mysql table that looks like this:
1 value1 value2 3534
2 value1 value1 8456
3 value1 value2 3566
4 value1 value3 7345
5 value2 value3 6734
I need a query to select all the rows with distinct column 2 and 3, for example the output I want for this example will look like this:
1 value1 value2 3534
2 value1 value1 8456
4 value1 value3 7345
5 value2 value3 6734
i've found a few samples on how to do it but they all select distinct on each column individually.
Update 1
Better you use this against above.
SELECT id, col2, col3, col4
FROM yourtable
GROUP BY col2, col3;
Demo
The reason I am saying is because using CONCAT, I am not getting desired result in this case. First query is returning me 5 rows however CONCAT is returning me 4 rows which is INCORRECT.
Hope you got my point.
Assumed the columns in the table are (id, col2, col3, col4).
SELECT DISTINCT(CONCAT(col2, col3)) as "dummy column", id, col2, col3, col4
FROM yourtable
GROUP BY CONCAT(col2, col3);
OR
SELECT id, col2, col3, MIN(col4)
FROM yourtable
GROUP BY col2, col3;
live working example
Assuming that the first column is unique, you can do this:
SELECT id, col2, col3, col4
FROM yourtable
WHERE id IN
(
SELECT MIN(id)
FROM yourtable
GROUP BY col2, col3
)
See it working online: sqlfiddle
Assuming the columns in the table are (id, col1, col2, col3), you could:
SELECT *
FROM YourTable yt
JOIN (
SELECT MIN(id) as minid
FROM YourTable
GROUP BY
col1, col2
) filter
ON filter.minid = yt.id
This query makes sure that the combination of column1 and column2 is unique, while selecting the minimum value of column three
SELECT col1, col2, MIN(col3)
FROM yourTable
GROUP BY col1, col2
THe simplest query for this is
SELECT col1, col2, MIN(col3)
FROM myTable
GROUP BY col1, col2
Using the group by method is returning me extra rows, where as explicitly checking each field although longer returns the same no of records as count(Distinct ..)
SELECT id, col2, col3, col4
FROM yourtable yt
WHERE id =
(
SELECT MIN(id)
FROM yourtable yt1
WHERE yt.col2 = yt1.col2
AND yt.col3 = yt1.col3
)