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CHECK constraint in MySQL is not working
...rigger...
mysql> delimiter //
mysql> CREATE TRIGGER trig_sd_check BEFORE INSERT ON Customer
-> FOR EACH ROW
-> BEGIN
-> IF NEW.SD<0 THEN
-> SET NEW.SD=0;
-> END IF;
-> END
-> //
mysql> delimiter ;
Hope that helps.
...
Difference between “read commited” and “repeatable read”
...a simple task like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any data. A concurrent tran...
Change default text in input type=“file”?
...
Personally, because most users stick to their browser of choice, and therefore are probably used to seeing the control in the default rendition, they'd probably get confused if they saw something different (depending on the types of users you're dealing with).
...
Getting “Skipping JaCoCo execution due to missing execution data file” upon executing JaCoCo
... the ways to do this in case of maven-surefire-plugin - is to
use syntax for late property evaluation:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<argLine>@{argLine} -your ...
How to search for a part of a word with ElasticSearch
...ve recently started using ElasticSearch and I can't seem to make it search for a part of a word.
10 Answers
...
Index on multiple columns in Ruby on Rails
...at the beginning. i.e. if you index on [:user_id, :article_id], you can perform a fast query on user_id or user_id AND article_id, but NOT on article_id.
Your migration add_index line should look something like this:
add_index :user_views, [:user_id, :article_id]
Question regarding 'unique' ...
Socket.io rooms difference between broadcast.to and sockets.in
...
in none. Different name for same thing.
– mike_hornbeck
Jun 18 '13 at 14:56
...
PHP + MySQL transactions examples
...the function used to execute a query, and throw an exception yourself.
Unfortunately, there is no magic involved. You cannot just put an instruction somewhere and have transactions done automatically: you still have to specific which group of queries must be executed in a transaction.
For example,...
How can I do width = 100% - 100px in CSS?
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I found when I was using calc(100% - 6px) for example it was displaying as calc(94%), I had to escape it as follows and now it works width: calc(~"100% - 6px");
– nsilva
Apr 19 '16 at 12:53
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How to get the Android device's primary e-mail address
...and contact data. If you misuse a user's email address or other personal information, bad things can happen.
Method A: Use AccountManager (API level 5+)
You can use AccountManager.getAccounts or AccountManager.getAccountsByType to get a list of all account names on the device. Fortunately, for cer...