Table 1
Col1
Col2
Date
A
B
02/25/2020
A
B
02/25/2020
A
B
03/20/2020
A
C
02/21/2020
select *
from Table1
where Date between 2020-02-20 and 2020-02-27
Table 2
Col1
Col2
Date
A
B
03/20/2020
D
E
03/20/2020
Need to compare the Table 1 to Table 2 and if col1 and col 2 values are same that records should not display from the Table 1
So the output shpuld be from Table1
Col1
Col2
Date
A
C
03/20/2020
Use an outer join:
select a.*
from Table1 a
left join Table2 b on a.col1 = b.col1
and a.col2 = b.col2
where Date between '2020-02-20' and '2020-02-27'
and b.col1 is null
whose where clause filters for rows that do not have a join.
Selecting the rows from Table1 which does not exist in Table2 based on Col1 and Col2.
SELECT * FROM Table1 T1
WHERE NOT EXISTS (
SELECT 1 FROM Table2 T2
WHERE T1.col1 = T2.col1
AND T1.col2 = T2.col2
)
AND T1.Date between '2020-02-20' and '2020-02-27'
Related
I want to join two tables that have the same columns, with an overlapping id column, but merge based on if table1.col1 >= table2.col1. This is in SQL.
If table1.col1>=table2.col1, use the columns from table1.
If table1.col1< table2.col1, then use columns from table2.
If the id does not exist in table1 but exists in table2, use the columns from table2
If the id does not exist in table2 but exists in table1, use the columns from table1
For example:
Table1:
id
col1
col2
col3
A
3
5
4
B
1
2
3
C
8
9
7
Table2:
id
col1
col2
col3
A
2
5
6
B
5
7
8
D
2
3
4
I want the result to be:
id
col1
col2
col3
A
3
5
4
B
5
7
8
C
8
9
7
D
2
3
4
I have tried union, full outer join, and CASE statements, but am stuck
I think individual case expressions for each column might be best:
select id,
(case when t1.col1 < t2.col1 then t2.col1 else t1.col1 end) as col1,
(case when t1.col1 < t2.col1 then t2.col2 else t1.col2 end) as col2,
(case when t1.col1 < t2.col1 then t2.col3 else t1.col3 end) as col3
from t1 full join
t2
using (id);
If that is cumbersome, another approach uses not exists:
select t1.*
from t1
where not exists (select 1
from t2
where t2.id = t1.id and t2.col1 > t1.col1
)
union all
select t2.*
from t2
where not exists (select 1
from t1
where t2.id = t1.id and t1.col1 >= t2.col1
);
Another solution:
SELECT DISTINCT ON (id) *
FROM (
SELECT *
FROM table1
UNION ALL
SELECT *
FROM table2
) AS aux
ORDER BY id, col1 DESC;
I tried it in Postgresql.
I have the following table:
ID COl1 COl2
1 13 15
2 13 16
3 13 17
4 17 13
What I need is to select all rows where Col1 value is available in Col2 and vice versa.
This case only ROW 4 or ROW 3 should be returned. They have same values (13 17).
Take it as col1 is Buyer and col2 is Seller
I want to know who are the users who bought / sell from EACH OTHER.
if user a bought from user b, user b should buy from user a in order to be returned.
SELECT
a.*
FROM
yourTable a
INNER JOIN
yourTable b
ON a.Col1 = b.Col2
AND a.Col2 = b.Col1
AND a.id != b.id
This can be done by using sub queries:
SELECT ID, COl1, COl2
FROM table1 WHERE COl1 IN (SELECT DISTINCT COl2 FROM table1)
UNION
SELECT ID, COl1, COl2
FROM table1 WHERE COl2 IN (SELECT DISTINCT COl1 FROM table1)
This sounds like exists:
select t.*
from t
where exists (select 1 from t t2 where t2.col1 = t.col2) and
exists (select 1 from t t2 where t2.col2 = t.col1) ;
If you want them in the same row, I would still use exists:
select t.*
from t
where exists (select 1 from t t2 where t2.col1 = t.col2 AND t2.col2 = t.col1) ;
I recommend this over a self-join because it will not generate multiple rows if there are multiple examples of the buyers and sellers on either side.
This also works
SELECT * FROM your_table WHERE
col1 IN (SELECT col2 FROM your_table)
AND
col2 IN (SELECT col1 FROM your_table);
I have the following data: column 1 with many category and column 2 with values for each category. I need to convert or pivot this information to show each value for category group across multiple columns.
col1 col2
----------------
1 a
2 b
2 c
2 d
3 e
3 f
4 g
4 h
And need this result:
col1 col2 col3 col4 col5 col6
-----------------------------------------------
1 a
2 b c d
3 e f
4 g h
There are no more than seven values per tb1 count(column 2) group(column 1). All values from tb1 column 2 are different and about + 50 records.
You want to pivot your table, but your table doesn't currently contain the field that you want to pivot on ("col1", "col2", "col3", etc...). You need a row number, partitioned by col1. The Jet database does not provide a ROW_NUMBER function, so you have to fake it by joining the table to itself:
select t1.col1, t1.col2, count(*) as row_num
from [Sheet1$] t1
inner join [Sheet1$] t2 on t2.col1 = t1.col1 and t2.col2 <= t1.col2
group by t1.col1, t1.col2
Now you can pivot on row_num:
transform Min(x.col2) select x.col1
from(
select t1.col1, t1.col2, count(*) as row_num
from [Sheet1$] t1
inner join [Sheet1$] t2 on t2.col1 = t1.col1 and t2.col2 <= t1.col2
group by t1.col1, t1.col2
) x
group by x.col1
pivot x.row_num
Table:
Col1 Col2
1 2
1 3
1 4
2 2
2 3
first need to check all rows with col2 = 4
Then need to select all rows with values col1
The result should be:
1 2
1 3
1 4
Off the top of my head
SELECT A.* FROM MyTable A JOIN MyTable B ON A.Col1 = B.Col1 WHERE B.Col2 = 4
I think you want this:
select t.*
from t
where t.col1 in (select t2.col1 from t t2 where t2.col2 = 4);
This query checks on both columns, where col2 = 4 and col1 = 1, from what i can understand in your description.
SELECT t1.col1, t2.col2 FROM Table t1
WHERE t1.col2 = 4
UNION
SELECT t2.col1, t2.col2 FROM Table t2
WHERE t2.col1 = 1
I have two tables
t1
col1 col2
A 1
A 2
B 1
C 2
t2
col1
1
2
I want to retrieve the records in tab1 which match all the records in tab2,
For the given scenario, I want to output A only because it has both 1 and 2 in col2 where as B and C has only a 1 or a 2 (not both).
You can write the query this way:
select t1.col1
from t1 join
t2
on t1.col2 = t2.col1
group by t1.col1
having count(distinct t1.col2) = (select count(distinct t2.col1) from t2);
This counts the number of matching values in the first table and compares it to the total number of values in the table.