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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...o which a VARCHAR's length can be extended through the use of online ALTER TABLE. Consequently, I derived those numbers by creating a table with a varchar(2) charset utf8 column and seeing how far I was able to extend it given ALGORITHM=INPLACE.
– antak
Apr 11...
How to list all properties of a PowerShell object
...Shell provides a set of formatting instructions that can affect either the table or list formats. These are usually meant to limit the display of reams of properties down to just the essential properties. However there are times when you really want to see everything. In those cases Format-List * wi...
Learning Ant path style
...re is how to navigating to this part of documentation from the Ant Manual: Table of Contents => "Concepts and Types" => [List of Types] left menu section => "Directory-based Tasks" => [Patterns] page section.
– informatik01
Feb 25 '14 at 14:55
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Convert char to int in C and C++
...e subtracted from each other. Since 0 comes directly before 1 in the ascii table (and so on until 9), the difference between the two gives the number that the character a represents.
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What is `related_name` used for in Django?
...ted name is a must in case there 2 FKs in the model that point to the same table. For example in case of Bill of material
@with_author
class BOM(models.Model):
name = models.CharField(max_length=200,null=True, blank=True)
description = models.TextField(null=True, blank=True)
tomateria...
MySQL: Set user variable from result of query
...r = @user;
SELECT * FROM user WHERE `group` = @group;
Test case:
CREATE TABLE user (`user` int, `group` int);
INSERT INTO user VALUES (123456, 5);
INSERT INTO user VALUES (111111, 5);
Result:
SET @user := 123456;
SELECT @group := `group` FROM user WHERE user = @user;
SELECT * FROM user WHERE `...
Add alternating row color to SQL Server Reporting services report
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Go to the table row's BackgroundColor property and choose "Expression..."
Use this expression:
= IIf(RowNumber(Nothing) Mod 2 = 0, "Silver", "Transparent")
This trick can be applied to many areas of the report.
And in .NET 3.5+ Y...
Get list of databases from SQL Server
...
@Gia It does exist as a backwards compatablity view. msdn.microsoft.com/en-us/library/ms179900%28v=SQL.110%29.aspx
– Chris Diver
Aug 7 '11 at 22:26
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How can I stop a Postgres script when it encounters an error?
... Yes, and not to forget continuing when it encounters DDL Create table errrors... (version: postrgres 10). Yes, it skips one table and goes onto the others...
– JL Peyret
Jan 23 '19 at 9:30
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Mod of negative number is melting my brain
...he way, here's a reason why using a single % might be a good idea. See the table What things cost in managed code in the article Writing Faster Managed Code: Know What Things Cost. Using % is similarly expensive to int div listed in the table: about 36 times more expensive than adding or subtracting...