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INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
Why is it important to override GetHashCode when Equals method is overridden?
...yeah, looks like I left them out when I copy-pasted the code from a region selection in Visual Studio. I also thought people would figure it out both.
– Trap
Apr 13 '12 at 12:11
3
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How can I change IIS Express port for a site
...
In Solution Explorer, right-click the name of the application and then select Properties.
Click the Web tab.
In the Servers section, under Use Local IIS Web server, in the Project URL box change the port number.
To the right of the Project URL box, click Create Virtual Directory, and then ...
Is there a standard for storing normalized phone numbers in a database?
...
A good old nvarchar(42) with a bit of validation /^+?[0-9 -\.\(\)#*]{4,41}$/ works very well!
– SandRock
Apr 5 '12 at 20:19
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Get table column names in MySQL?
...DESCRIBE my_table;
Or in newer versions you can use INFORMATION_SCHEMA:
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'my_database' AND TABLE_NAME = 'my_table';
Or you can use SHOW COLUMNS:
SHOW COLUMNS FROM my_table;
...
Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
...
TFS: Updating branch with changes from main
...
From Visual Studio, open Source Control Explorer:
View | Team Explorer
Select your Team Project from Team Explorer, expand it, and double click Source Control
In the left-hand pane of Source Control Explorer, select your Team Project.
In the right-hand pane, find your mainline branch, right-clic...
erb, haml or slim: which one do you suggest? And why? [closed]
...g new (like HAML) I'd go for HAML. It is a lot more ruby-friendly, reduces char count by much and a lot more readable than ERB.
For example (taken from official HAML site):
In ERB your view will look like this:
<div id="profile">
<div class="left column">
<div id="date">&l...
How to version control a record in a database
...tDate of the second record.
When you want to view the current record, you select the one where endDate is null.
This is sometimes called a type 2 Slowly Changing Dimension.
See also TupleVersioning
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Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...