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When/Why to use Cascading in SQL Server?
...eal key rather than a surrogate key (identity/autoincrement column) across tables.
The canonical example for Cascade Update is when you have a mutable foreign key, like a username that can be changed.
You should not use Cascade Update with keys that are Identity/autoincrement columns.
Cascade Updat...
How do I horizontally center a span element inside a div
...
another option would be to give the span display:table; and center it via margin:0 auto;
span {
display:table;
margin:0 auto;
}
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What does the “@” symbol do in Powershell?
...l V2, @ is also the Splat operator.
PS> # First use it to create a hashtable of parameters:
PS> $params = @{path = "c:\temp"; Recurse= $true}
PS> # Then use it to SPLAT the parameters - which is to say to expand a hash table
PS> # into a set of command line parameters.
PS> dir @para...
How to test an SQL Update statement before running it?
...man/5.0/en/commit.html
For example:
START TRANSACTION;
SELECT * FROM nicetable WHERE somthing=1;
UPDATE nicetable SET nicefield='VALUE' WHERE somthing=1;
SELECT * FROM nicetable WHERE somthing=1; #check
COMMIT;
# or if you want to reset changes
ROLLBACK;
SELECT * FROM nicetable WHERE somthing=1...
How do I use LINQ Contains(string[]) instead of Contains(string)
...ids = arrayofuids.Select(id => int.Parse(id)).ToList();
var selected = table.Where(t => uids.Contains(t.uid));
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How to check if a database exists in SQL Server?
...ing the INFORMATION_SCHEMA views rather than directly accessing the system tables.
– mwigdahl
Mar 24 '09 at 20:09
4
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How to define a custom ORDER BY order in mySQL
...age,'ENU','JPN','DAN'), ID
Note however, that
It makes your SQL less portable, as other DBMSs might not have such function
When your list of languages (or other values to sort by) gets much longer, it's better to have a separate table with sortorder column for them, and join it to your queries fo...
SQL select only rows with max value on a column [duplicate]
I have this table for documents (simplified version here):
27 Answers
27
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What's the difference between VARCHAR and CHAR?
...: when Anon. says "your content is a fixed size" it means the rows of your table must contain all fixed size fields. You get no performance improvement if you use CHAR against VARCHAR in one field, but the table contains other fields that are VARCHAR.
– Marco Demaio
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How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
... be only 1 instance of the base A class not 2.
Your type D would have 2 vtable pointers (you can see them in the first diagram), one for B and one for C who virtually inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are...