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MySQL Query GROUP BY day / month / year
... Simple complete example: SELECT count(*), record_date FROM anytable WHERE anytable.anycolumn = 'anycondition' GROUP BY YEAR(record_date), month(record_date); note: record_date is a date type TIMESTAMP
– renedet
Jul 25 '17 at 18:35
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What are the best practices for using a GUID as a primary key, specifically regarding performance?
I have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, b...
Insert Data Into Temp Table with Query
...query that outputs current data, and I would like to insert it into a Temp table, but am having some issues doing so. Would anybody have some insight on how to do this?
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How to map a composite key with JPA and Hibernate?
...// getters, setters
}
The IdClass annotation maps multiple fields to the table PK.
With EmbeddedId
The class for the composite primary key could look like (could be a static inner class):
@Embeddable
public class TimePK implements Serializable {
protected Integer levelStation;
protecte...
Search for all occurrences of a string in a mysql database [duplicate]
...how to locate all occurrences of a url in a database. I want to search all tables and all fields. But I have no idea where to start or if it's even possible.
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What is SELF JOIN and when would you use it? [duplicate]
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You use a self join when a table references data in itself.
E.g., an Employee table may have a SupervisorID column that points to the employee that is the boss of the current employee.
To query the data and get information for both people in one row,...
PHP code to convert a MySQL query to CSV [closed]
...MINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $select ) or die ( "Sql error : " . mysql_error( ) );
$fi...
Should MySQL have its timezone set to UTC?
...`timestamp_field`, @@session.time_zone, '+00:00') AS `utc_datetime`
FROM `table_name`
You can also set the sever or global or current session timezone to UTC and then select the timestamp like so:
SELECT `timestamp_field` FROM `table_name`
To select the current datetime in UTC:
SELECT UTC_TIM...
How can I remove specific rules from iptables?
...l HTTP and HTTPS services on the ports 8006 and 8007 respectively. I use iptables to "activate" the server; i.e. to route the incoming HTTP and HTTPS ports:
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What's the fastest way to do a bulk insert into Postgres?
...e as CSV formatted mapping in PG query statement's. You can try for Big Table?
– Elyor
Sep 9 '14 at 2:03
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