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Is asynchronous jdbc call possible?
... busy/blocked per concurrent request.
If the underlying database drivers (MySql?) offers a means to intercept the socket creation (see SocketFactory) then I imagine it would be possible to build an async event driven database layer on top of the JDBC api but we'd have to encapsulate the whole JDBC ...
Should Gemfile.lock be included in .gitignore?
...ee CRM.
My preference is postgres, but we want the default database to be mysql2.
In this case, Gemfile.lock still needs be checked in with the default set of gems, but I need to ignore changes that I have made to it on my machine. To accomplish this, I run:
git update-index --assume-unchanged G...
How do I get a raw, compiled SQL query from a SQLAlchemy expression?
...o %s or other variables waiting to be bound by the statement compiler or MySQLdb dialect engine, etc).
12 Answers
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Master-master vs master-slave database architecture?
...uture. I came across
Master-Slave Replication
Master-Master Replication
MySQL Cluster
I have decided to settle for using MySQL Cluster for my use case. However please see below for the various pros and cons that I have compiled
1. Master-Slave Replication
Pros
Analytic applications can rea...
How do I pass JavaScript variables to PHP?
... <?php
$query = "SELECT * FROM salarie";
$result = mysql_query($query);
if ($result) :
?>
<select id="salarieids" name="salarieid">
<?php
while ($row = mysql_fetch_assoc($result)) {
echo '<option val...
Using LIMIT within GROUP BY to get N results per group?
... behavior of both quirks is not guaranteed. Revised answer as follows.
In MySQL 5.x you can use poor man's rank over partition to achieve desired result. Just outer join the table with itself and for each row, count the number of rows lesser than it. In the above case, lesser row is the one with hi...
Sync data between Android App and webserver [closed]
...logic for database like: How to sync SQLite database on Android phone with MySQL database on server?
Best Luck to all new learner. :)
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SQL query to group by day
... (from Q8-Coder):
GROUP BY dateadd(DAY,0, datediff(day,0, created))
For MySQL:
GROUP BY year(datefield), month(datefield), day(datefield)
or better (from Jon Bright):
GROUP BY date(datefield)
For Oracle:
GROUP BY to_char(datefield, 'yyyy-mm-dd')
or faster (from IronGoofy):
GROUP BY trun...
Update a column value, replacing part of a string
I have a table with the following columns in a MySQL database
6 Answers
6
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...
@davidblaine, MySQL has a function GROUP_CONCAT() for that. dev.mysql.com/doc/refman/5.5/en/… But in standard SQL, each column should contain only one value. That's fundamental to relational theory too.
– Bill Kar...