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MySQL error: key specification without a key length
...d, and the trick is to choose a number N that’s long enough to give good selectivity, but short enough to save space. The prefix should be long enough to make the index nearly as useful as it would be if you’d indexed the whole column.
Before we go further let us define some important terms. In...
Visual Studio hot keys change occasionally, specifically F6 vs Ctrl-Shift-B for building. WHY?
...
This is because you might have selected "General Development Settings" as your default environment settings for your Visual Studio (which usually we do on the first launch of VS after installing it as it pops up a dialogue box to choose default environment...
How to change collation of database, table, column?
...he OP asked:
How to change collation of database, table, column?
The selected answer just states it on table level.
Changing it database wide:
ALTER DATABASE <database_name> CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
Changing it per table:
ALTER TABLE <table_name> CON...
How do I add an existing Solution to GitHub from Visual Studio 2013
...
OK this worked for me.
Open the solution in Visual Studio 2013
Select File | Add to Source Control
Select the Microsoft Git Provider
That creates a local GIT repository
Surf to GitHub
Create a new repository DO NOT SELECT Initialize this repository with a README
That creates an em...
How do I use prepared statements in SQlite in Android?
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@jasonhudgins Why not just replace your SELECT with an INSERT? I just came from this thread, where you've confused a beginner
– keyser
May 3 '14 at 15:29
...
Reset auto increment counter in postgres
... Does anyone know why ALTER SEQUENCE product_id_seq RESTART WITH (SELECT MAX(id) from product); Doesn't work? The only way I found is to use two separate queries.
– Chris Huang-Leaver
Dec 20 '18 at 3:14
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Oracle “(+)” Operator
...dize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOINs.
It should also be noted that even though the (+) works, Oracle recommends not using it:
Oracle re...
Unpivot with column name
...hould be able to use the following which includes the subject in the final select list:
select u.name, u.subject, u.marks
from student s
unpivot
(
marks
for subject in (Maths, Science, English)
) u;
See SQL Fiddle with demo
...
How to create P12 certificate for iOS distribution
...hain Access where it will be matched up with the private key. You can then select the cert, and open the arrow to also select the private key and export them together as a .p12 file from Keychain Access.
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Current executing procedure name
...
You may try this:
SELECT OBJECT_NAME(@@PROCID)
Update: This command is still valid on SQL Server 2016.
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