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Creation timestamp and last update timestamp with Hibernate and MySQL
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I would do this using a MySQL trigger so that even if the full entity is not saved or is modified by any external application or manual query, it'll still update these fields.
– Webnet
Jul 25 '13 at 12:09
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Unique constraint that allows empty values in MySQL
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Yes, you can do this. See the MySQL reference (version 5.5).
A UNIQUE index creates a constraint such that all values in the index must be distinct. An error occurs if you try to add a new row with a key value that matches an existing row. For all eng...
How to move columns in a MySQL table?
Currently I am having the following MySQL table: Employees (empID, empName, department);
4 Answers
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MySQL/SQL: Group by date only on a Datetime column
...son. I would expect it to fail anywhere else as well. Can you confirm that MySQL actually handles this query?
– Tomalak
Dec 14 '08 at 15:56
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When and why are database joins expensive?
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MySQL, Oracle, SQL Server, Sybase, postgreSQL,etc. care not the order of joins. I've worked with DB2 and it also, to my knowledge, doesn't care what order you put them in. This is not helpful advice in the general case
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MySQL convert date string to Unix timestamp
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You will certainly have to use both STR_TO_DATE to convert your date to a MySQL standard date format, and UNIX_TIMESTAMP to get the timestamp from it.
Given the format of your date, something like
UNIX_TIMESTAMP(STR_TO_DATE(Sales.SalesDate, '%M %e %Y %h:%i%p'))
Will gives you a valid timestam...
How to log source file name and line number in Python
...way that sends debug logging to standard out:
import logging
import sys
root = logging.getLogger()
root.setLevel(logging.DEBUG)
ch = logging.StreamHandler(sys.stdout)
ch.setLevel(logging.DEBUG)
FORMAT = "[%(filename)s:%(lineno)s - %(funcName)20s() ] %(message)s"
formatter = logging.Formatter(FOR...
Illegal mix of collations MySQL Error
...E your_table_name CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;
MySQL sneaks swedish in there sometimes for no sensible reason.
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How to convert timestamp to datetime in MySQL?
How to convert 1300464000 to 2011-03-18 16:00:00 in MySQL?
5 Answers
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Two single-column indexes vs one two-column index in MySQL?
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"MySQL can use multiple-column indexes for queries that test all the columns in the index, or queries that test just the first column, the first two columns, the first three columns, and so on. If you specify the columns in th...