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How to use DISTINCT and ORDER BY in same SELECT statement?
..., and use a GROUP BY to make the DISTINCT work.
Try something like this:
SELECT DISTINCT Category, MAX(CreationDate)
FROM MonitoringJob
GROUP BY Category
ORDER BY MAX(CreationDate) DESC, Category
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Is there a combination of “LIKE” and “IN” in SQL?
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An example table:
SQL> create table mytable (something)
2 as
3 select 'blabla' from dual union all
4 select 'notbla' from dual union all
5 select 'ofooof' from dual union all
6 select 'ofofof' from dual union all
7 select 'batzzz' from dual
8 /
Table created.
The origin...
Insertion Sort vs. Selection Sort
I am trying to understand the differences between Insertion Sort and Selection Sort.
20 Answers
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How do I query if a database schema exists
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Are you looking for sys.schemas?
IF NOT EXISTS (SELECT * FROM sys.schemas WHERE name = 'jim')
BEGIN
EXEC('CREATE SCHEMA jim')
END
Note that the CREATE SCHEMA must be run in its own batch (per the answer below)
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How do I make a placeholder for a 'select' box?
...s which is working out just fine. But I'd like to use a placeholder for my selectboxes as well. Of course I can just use this code:
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How to concatenate text from multiple rows into a single text string in SQL server?
...y, John, Sam
2 Alaina, Edward
I used the following T-SQL:
SELECT Main.SubjectID,
LEFT(Main.Students,Len(Main.Students)-1) As "Students"
FROM
(
SELECT DISTINCT ST2.SubjectID,
(
SELECT ST1.StudentName + ',' AS [text()]
FR...
Is there a way to loop through a table variable in TSQL without using a cursor?
...impler code.
Depending on your data it may be possible to loop using just SELECT statements as shown below:
Declare @Id int
While (Select Count(*) From ATable Where Processed = 0) > 0
Begin
Select Top 1 @Id = Id From ATable Where Processed = 0
--Do some processing here
Update ATa...
PostgreSQL DISTINCT ON with different ORDER BY
...llowing approaches:
The general solution that should work in most DBMSs:
SELECT t1.* FROM purchases t1
JOIN (
SELECT address_id, max(purchased_at) max_purchased_at
FROM purchases
WHERE product_id = 1
GROUP BY address_id
) t2
ON t1.address_id = t2.address_id AND t1.purchased_at = t2...
Import / Export database with SQL Server Server Management Studio
... if you want to also export the data, on the "Set Scripting Options" step, select the "Advanced" button and change "Types of data to script" from "Schema Only" to "Data Only" or "Schema and Data".
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how to exclude null values in array_agg like in string_agg using postgres?
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SQL Fiddle
select
id,
(select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users,
(select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users
from (
SELE...