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Drop all tables whose names begin with a certain string
...n one in the database.
DECLARE @cmd varchar(4000)
DECLARE cmds CURSOR FOR
SELECT 'drop table [' + Table_Name + ']'
FROM INFORMATION_SCHEMA.TABLES
WHERE Table_Name LIKE 'prefix%'
OPEN cmds
WHILE 1 = 1
BEGIN
FETCH cmds INTO @cmd
IF @@fetch_status != 0 BREAK
EXEC(@cmd)
END
CLOSE cmds;
DEA...
Cannot simply use PostgreSQL table name (“relation does not exist”)
....
In other words, the following fails:
CREATE TABLE "SF_Bands" ( ... );
SELECT * FROM sf_bands; -- ERROR!
Use double-quotes to delimit identifiers so you can use the specific mixed-case spelling as the table is defined.
SELECT * FROM "SF_Bands";
Re your comment, you can add a schema to th...
How to check if a Constraint exists in Sql server?
...
try this:
SELECT
*
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS
WHERE CONSTRAINT_NAME ='FK_ChannelPlayerSkins_Channels'
-- EDIT --
When I originally answered this question, I was thinking "Foreign Key" because the o...
Difference between natural join and inner join
...+----------+
The INNER JOIN of TableA and TableB on Column1 will return
SELECT * FROM TableA AS a INNER JOIN TableB AS b USING (Column1);
SELECT * FROM TableA AS a INNER JOIN TableB AS b ON a.Column1 = b.Column1;
+------------+-----------+---------------------+
| a.Column1 | a.Column2 | ...
postgresql list and order tables by size
...
select table_name, pg_relation_size(quote_ident(table_name))
from information_schema.tables
where table_schema = 'public'
order by 2
This shows you the size of all tables in the schema public if you have multiple schemas, y...
Which are more performant, CTE or temporary tables?
...(A INT IDENTITY PRIMARY KEY, B INT , F CHAR(8000) NULL);
INSERT INTO T(B)
SELECT TOP (1000000) 0 + CAST(NEWID() AS BINARY(4))
FROM master..spt_values v1,
master..spt_values v2;
Example 1
WITH CTE1 AS
(
SELECT A,
ABS(B) AS Abs_B,
F
FROM T
)
SELECT *
FROM CTE1
WHERE A = 780
...
How do I set the value property in AngularJS' ng-options?
...following forms:
For array data sources:
label for value in array
select as label for value in array
label group by group for value in array
select as label group by group for value in array track by trackexpr
For object data sources:
label for (key , value) in object
select as la...
How to change Android Studio's editor font?
...TRL + mouse wheel which is really easy to use it !!!
To use this feature select File -> Settings -> Editor -> General -> select the checkbox of Change the font size (Zoom) with Ctrl + Mouse Wheel
I hope it's helpful.
...
Which method performs better: .Any() vs .Count() > 0?
...re generated SQLs. Beauties as you can see ;)
ANY:
exec sp_executesql N'SELECT TOP (1)
[Project2].[ContactId] AS [ContactId],
[Project2].[CompanyId] AS [CompanyId],
[Project2].[ContactName] AS [ContactName],
[Project2].[FullName] AS [FullName],
[Project2].[ContactStatusId] AS [ContactStatusI...
jQuery - setting the selected value of a select control via its text description
I have a select control, and in a javascript variable I have a text string.
21 Answers
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