The Kusto operator union * gets all the tables from a database , but once the data is clubbed together , we have no way to tell which rows came from where. Is there a way to force union * to add a column to the output that will contain name of the table a specific row came from ?
You can use withsource (see in documentation)
execute query
union withsource=TableName *
| summarize count() by TableName
| top 2 by count_
Related
I am using Oracle SQL Developer
I am combining two output of two queries using union all operator.
I am giving simple example because I cant share whole query (Working
for Bank)
select * from tb1 where rownum between &range1 and &range2
Union all
select * from tb2 where rownum between &range1 and &range2
first query gives all credit transaction, second query gives Sum of Debit.
but I found wrong debit amount using above syntax.
when i use below syntax it gives correct Output
select * from tb1 where row_num between &range1 and &range2
Union all------------bug
select * from tb2 where row_num between &range3 and &range4
I just placed comment after union all, and this giving correct output.
I just cant understand how this can be possible?
I have a SQLite table where one column contains a JSON array containing 0 or more values. Something like this:
id|values
0 |[1,2,3]
1 |[]
2 |[2,3,4]
3 |[2]
What I want to do is "unfold" this into a list of all distinct values contained within the arrays of that column.
To start, I am using the JSON1 extension's json_each function to extract a table of values from a row:
SELECT
value
FROM
json_each(
(
SELECT
values
FROM
my_table
WHERE
id == 2
)
)
Where I can vary the id (2, above) to select any row in the table.
Now, I am trying to wrap this in a recursive CTE so that I can apply it to each row across the entire table and union the results. As a first step I replicated (roughly) the results from above as follows:
WITH RECURSIVE result AS (
SELECT null
UNION ALL
SELECT
value
FROM
json_each(
(
SELECT
values
FROM
my_table
WHERE
id == 2
)
)
)
SELECT * FROM result;
As the next step I had originally planned to make id a variable and increment it (in a similar manner to the first example in the documentation, but haven't been able to get that to work.
I have gone through the other examples in the documentation, but they are somewhat more complex and I haven't been able to distill those down to see how they might apply to this problem.
Can someone provide a simple example of how to solve this (or a similar problem) with a recursive CTE?
Of course, my goal is to solve the problem with or without CTEs so Im also happy to hear if there is a better way...
You do not need a recursive CTE for this.
To call json_each for multiple source rows, use a join:
SELECT t1.id, t2.value
FROM my_table AS t1
JOIN json_each((SELECT "values" FROM my_table WHERE id = t1.id)) AS t2;
I'm working on a database to keep track of packages I need for a personal project. I am also treating this as an exercise to teach myself database design and SQL. The database I am using has a schema like the following:
CREATE TABLE packages
(
ID INTEGER PRIMARY KEY,
Name TEXT UNIQUE ON CONFLICT REPLACE NOT NULL ON CONFLICT IGNORE
);
CREATE TABLE dependencies
(
dependentPackage INTEGER REFERENCES pages(ID),
requiredPackage INTEGER REFERENCES pages(ID)
);
where the package referenced by dependencies.dependentPackage depends on the package referenced by dependencies.requiredPackage
I want a query with a column NumPackagesRequired, which returns a table that looks something like this:
packageName | NumDependencies
package1 | 6
package5 | 8
package9 | 1
I cannot achieve this by trying:
SELECT p.name AS packageName, count (d.requiredPackage) AS numDependencies
FROM packages p
JOIN dependencies d ON d.dependentPackage=p.ID;
because it returns only one row, containing the first package's name and the count of all the requirements.
I tried nesting a SELECT statement as a parameter to the count() function, but I still only got a single row of results. I have searched the sqlite documentation with no degree of luck.
How can I get a table like the one expected above?
When you are using GROUP BY, aggregate functions are computed over each group:
SELECT p.name AS packageName,
count (d.requiredPackage) AS numDependencies
FROM packages p
JOIN dependencies d ON d.dependentPackage=p.ID
GROUP BY p.name;
Alternatively, move the couting into a correlated subquery:
SELECT name AS packageName,
(SELECT count(*)
FROM dependencies
WHERE dependentPackage = packages.ID
) AS numDependencies
FROM packages;
I want to make a volatile table using teradata.
In the select statement I am using multiple columns from different tables.
However, some of the columns in the different tables have same names.
Therefore, I am getting a 'duplication column error'.
The question is - is there any workaround to bypass this error?
Is it possible to add for example table name to column name?
This is how my code looks:
CREATE MULTISET VOLATILE TABLE test
AS (
SEL *
FROM Table_A Left JOIN Table_B
...
)
WITH DATA
ON COMMIT PRESERVE ROWS
Instead of doing a select * , select individual column names and put aliases next to it. This will bypass the error.
A select all statement only works if you're working off one table. If you're retrieving all data from multiple tables, you've to specify that in your select statement.
CREATE MULTISET VOLATILE TABLE test AS
(
SELECT Table_A.*
, Table_B.*
FROM Table_A
LEFT JOIN Table_B ON ...
...
)
WITH DATA PRIMARY INDEX(«PI»)
ON COMMIT PRESERVE ROWS
I would like to run a query involving joining a table to a manually generated list but am stuck trying to generate the manual list. There is an example of what I am attempting to do below:
SELECT
*
FROM
('29/12/2014', '30/12/2014', '30/12/2014') dates
;
Ideally I would want my output to look like:
29/12/2014
30/12/2014
31/12/2014
What's your Teradata release?
In TD14 there's STRTOK_SPLIT_TO_TABLE:
SELECT *
FROM TABLE (STRTOK_SPLIT_TO_TABLE(1 -- any dummy value
,'29/12/2014,30/12/2014,30/12/2014' -- any delimited string
,',' -- delimiter
)
RETURNS (outkey INTEGER
,tokennum INTEGER
,token VARCHAR(20) CHARACTER SET UNICODE) -- modify to match the actual size
) AS d
You can easily put this in a Derived Table and then join to it.
inkey (here the dummy value 1) is a numeric or string column, usually a key. Can be used for joining back to the original row.
outkey is the same as inkey.
tokennum is the ordinal position of the token in the input string.
token is the extracted substring.
Try this:
select '29/12/2014'
union
select '30/12/2014'
union
...
It should work in Teradata as well as in MySql.