I´d like to add several rows stemming from another SQL query (different table) to a query result. e.g.:
SELECT mycol from mytable
# returns
mycol
1
4
6
SELECT anothercol from anothertable
#returns
anothercol
3
8
9
What I would like to obtain is:
myresult
1
4
6
3
8
9
Currently I do this kind of operation with statistical software packages, but I wonder if that is possible in MySQL somehow. It's often needed when merging time series from different sources. Is there a SQL way to do it?
Use the UNION statement.
It's something like:
(SELECT * FROM table WHERE column = 34)
UNION
(SELECT * FROM table WHERE column2 = 45);
Then you can add an ORDER BY at the end like:
(SELECT * FROM table WHERE column = 34)
UNION
(SELECT * FROM table WHERE column2 = 45)
ORDER BY column;
SELECT mycol
FROM mytable
UNION ALL
SELECT othercol
FROM othertable
This question might be helpful: Merge 2 tables for a SELECT query?
Related
I have this (3 int columns in one table)
Int1 Int2 Int3
---------------
1 2 3
I would like to run such query with another someTable:
SELECT * FROM someTable WHERE someInt NOT IN (1,2,3)
where 1,2,3 are list of INTs converted to a list that I can use with SELECT * NOT IN statement
Any suggestions how to achieve this without stored procedures in Micorosft SQL Server 2019 ?
If you want rows in some table that are not in one of three columns of another table, then use not exists:
select t.*
from sometable t
where not exists (select 1
from t t2
where t.someint in (t2.int1, t2.int2, t2.int3)
);
The subquery returns a row where there is a match. The outer query then rejects any rows with a match.
Seems like you actually want a NOT EXISTS?
SELECT {Your Columns}
FROM dbo.someTable sT
WHERE NOT EXISTS (SELECT 1
FROM dbo.oneTable oT
WHERE sT.someInt NOT IN (oT.int1,oT.int2,oT.int3));
An alternative method would be to unpivot the data, and then use an equality operator:
SELECT {Your Columns}
FROM dbo.someTable sT
WHERE NOT EXISTS (SELECT 1
FROM dbo.oneTable oT
CROSS APPLY (VALUES(oT.int1),(oT.int2),(oT.int3))V(I)
WHERE V.I = sT.someInt);
I am new to sql and are trying to combine a column value from three different tables and combine to one row in DB2 Warehouse on Cloud. Each table consists of only one row and unique column name. So what I want to is just join these three to one row their original column names.
Each table is built from a statement that looks like this:
SELECT SUM(FUEL_TEMP.FUEL_MLAD_VALUE) AS FUEL
FROM
(SELECT ML_ANOMALY_DETECTION.MLAD_METRIC AS MLAD_METRIC, ML_ANOMALY_DETECTION.MLAD_VALUE AS FUEL_MLAD_VALUE, ML_ANOMALY_DETECTION.TAG_NAME AS TAG_NAME, ML_ANOMALY_DETECTION.DATETIME AS DATETIME, DATA_CONFIG.SYSTEM_NAME AS SYSTEM_NAME
FROM ML_ANOMALY_DETECTION
INNER JOIN DATA_CONFIG ON
(ML_ANOMALY_DETECTION.TAG_NAME =DATA_CONFIG.TAG_NAME AND
DATA_CONFIG.SYSTEM_NAME = 'FUEL')
WHERE ML_ANOMALY_DETECTION.MLAD_METRIC = 'IFOREST_SCORE'
AND ML_ANOMALY_DETECTION.DATETIME >= (CURRENT DATE - 9 DAYS)
ORDER BY DATETIME DESC)
AS FUEL_TEMP
I have tried JOIN, INNER JOIN, UNION/UNION ALL, but can't get it to work as it should. How can I do this?
Use a cross-join like this:
create table table1 (field1 char(10));
create table table2 (field2 char(10));
create table table3 (field3 char(10));
insert into table1 values('value1');
insert into table2 values('value2');
insert into table3 values('value3');
select *
from table1
cross join table2
cross join table3;
Result:
field1 field2 field3
---------- ---------- ----------
value1 value2 value3
A cross join joins all the rows on the left with all the rows on the right. You will end up with a product of rows (table1 rows x table2 rows x table3 rows). Since each table only has one row, you will get (1 x 1 x 1) = 1 row.
Using UNION should solve your problem. Something like this:
SELECT
WarehouseDB1.WarehouseID AS TheID,
'A' AS TheSystem,
WarehouseDB1.TheValue AS TheValue
FROM WarehouseDB1
UNION
SELECT
WarehouseDB2.WarehouseID AS TheID,
'B' AS TheSystem,
WarehouseDB2.TheValue AS TheValue
FROM WarehouseDB2
UNION
WarehouseDB3.WarehouseID AS TheID,
'C' AS TheSystem,
WarehouseDB3.TheValue AS TheValue
FROM WarehouseDB3
Ill adapt the code with your table names and rows if you tell me what they are. This kind of query would return something like the following:
TheID TheSystem TheValue
1 A 10
2 A 20
3 B 30
4 C 40
5 C 50
As long as your column names match in each query, you should get the desired results.
I know that it's possible in other SQL flavors (T-SQL) to "select" provided data without a table. Like:
SELECT *
FROM (VALUES (1,2), (3,4)) tbl
How can I do this using Teradata?
Teradata has strange syntax for this:
select t.*
from (select * from (select 1 as a, 2 as b) x
union all
select * from (select 3 as a, 4 as b) x
) t;
I don't have access to a TD system to test, but you might be able to remove one of the nested SELECTs from the answer above:
select x.*
from (
select 1 as a, 2 as b
union all
select 3 as a, 4 as b
) x
If you need to generate some random rows, you can always do a SELECT from a system table, like sys_calendar.calendar:
SELECT 1, 2
FROM sys_calendar.calendar
SAMPLE 10;
Updated example:
SELECT TOP 1000 -- Limit to 1000 rows (you can use SAMPLE too)
ROW_NUMBER() OVER() MyNum, -- Sequential numbering
MyNum MOD 7, -- Modulo operator
RANDOM(1,1000), -- Random number between 1,1000
HASHROW(MyNum) -- Rowhash value of given column(s)
FROM sys_calendar.calendar; -- Use as table to source rows
A couple notes:
make sure you pick a system table that will always be present and have rows
if you need more rows than are available in the source table, do a UNION to get more rows
you can always easily create a one-column table and populate it to whatever number of rows you want by INSERT/SELECT into it:
CREATE DummyTable (c1 INT); -- Create table
INSERT INTO DummyTable(1); -- Seed table
INSERT INTO DummyTable SELECT * FROM DummyTable; -- Run this to duplicate rows as many times are you want
Then use this table to create whatever resultset you want, similar to the query above with sys_calendar.calendar.
I don't have a TD system to test so you might get syntax errors...but that should give you a basic idea.
I am a bit late to this thread, but recently got the same error.
I solved this by simply using
select distinct 1 as a, 2 as b from DBC.tables
union all
select distinct 3 as a, 4 as b from DBC.tables
Here, DBC.tables is a DB backend table with a few rows only. So, the query runs fast as well
How can I get records from my table where any of a list of integers is in the range defined by columnA and columnB integer values?
I know about the IN operator when comparing against a column value instead of a range defined by a pair of columns.
For example: select * from mytable where mytable.colA in (1,3,5,6); would get all records where colA is either 1,3,5 or 6.
Is there anything like that for ranges? Or should I do like:
select * from mytable where 1 between mytable.colA and mytable.colb
OR
3 between mytable.colA and mytable.colb
OR
5 between mytable.colA and mytable.colb
OR
6 between mytable.colA and mytable.colb;
Maybe this way:
select distinct mytable.*
from mytable
join (select 1 nr union all select 3 union all select 5 union all select 6) n
on n.nr between mytable.colA and mytable.colb
Update:
Just tested on MariaDB (10.0.19) and a 1M-row indexed table.. Your original query is ways faster.
A common tactic is to set up a temporary table, and use that to join on your main table.
A simple way to set one up is like so:
DECLARE #TempList table (LookFor int not null)
INSERT #TempList (LookFor) values
(1)
,(3)
,(5)
,(6)
As this is a table, you can use querying logic to populate it.
Next up, join this into your target table. For your example above:
SELECT mt.*
from myTable mt
inner join #TempList tl
on tl.LookFor = mt.ColA
And, if I'm interpreting correctly, this might be what you're really looking for:
SELECT mt.*
from myTable mt
inner join #TempList tl
on tl.LookFor between mt.ColA and mt.ColB
I have the following two tables with data like so:
Table Values
var_label
1
2
2
1
3
Table Codes
var_code
1
2
4
2
I need to join these tables and get the distinct result. The var_label and var_code are equal pieces of data. I want to have the joined output like so:
MyColumn
1
2
3
4
Wht's the best way to do this?
Use UNION without ALL(implicit distinct) like so:
SELECT var_label AS MyColumn
FROM Values
UNION
SELECT var_code
FROM Codes
Live Demo
SELECT var_label
FROM Table1 as MyColumn
UNION
SELECT var_data as MyColumn
FROM Table2
you can give aliases for getting only one colum name.
SQLFiddle DEMO
SELECT distinct(var_label)
FROM Table1
UNION
SELECT distinct(var_data)
FROM Table2