Indexing datetime in MySQL

Posted by User1 on Stack Overflow See other posts from Stack Overflow or by User1
Published on 2010-05-11T17:11:00Z Indexed on 2010/05/11 17:14 UTC
Read the original article Hit count: 207

Filed under:

mysql

|

datetime

|

indexing

What is the best way to index a datetime in MySQL? Which method is faster:

Store the datetime as a double (via unix timestamp)
Store the datetime as a datetime

The application generating the timestamp data can output either format. Unfortunately, datetime will be a key for this particular data structure so speed will matter.

Also, is it possible to make an index on an expression? For example, index on UNIX_TIMESTAMP(mydate) where mydate is a field in a table and UNIX_TIMESTAMP is a mysql function. I know that Postgres can do it. I'm thinking there must be a way in mysql as well.

© Stack Overflow or respective owner

Related posts about mysql

How to remove MySQL completely with config and library files on ubuntu 12.04 gnome 3.0

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I tried everything till now: sudo apt-get remove mysql-server mysql-client mysql-common sudo apt-get purge mysql-server mysql-client mysql-common sudo apt-get autoremove and even more commands... But whenever I am trying to locate mysql. I get a no. of files related to mysql command: shell>>… >>> More
mysql: Cannot load from mysql.proc. The table is probably corrupted

as seen on Server Fault - Search for 'Server Fault'
Mysql was started: /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 but when I'm trying to do something: ERROR 1548 (HY000) at line 1: Cannot… >>> More
Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

as seen on Server Fault - Search for 'Server Fault'
A client of my IT-consulting service owns a web-development shop. He's been having problems with a Slackware 12.0 server running MySQL 5.0.67. The machine was set up by the client's sysadmin, who left on bad terms. My client no longer employs a sysadmin. As far as I can tell, the only copy of MySQL… >>> More
mysql: Bind on unix socket: Permission denied

as seen on Server Fault - Search for 'Server Fault'
Can't start mysql with: sudo /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 120222 13:40:48 mysqld_safe Starting mysqld daemon with databases… >>> More
MySQL – Learning MySQL Online in 6 Hours – MySQL Fundamentals in 320 Minutes

as seen on SQL Authority - Search for 'SQL Authority'
MySQL is one of the most popular database language and I have been recently working with it a lot. Data have no barrier and every database have their own place. I have been working with MySQL for quite a while and just like SQL Server, I often find lots of people asking me if I have a tutorial which… >>> More

Related posts about datetime

Finding begin and end of year/month/day/hour

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using the following snipped to find the begin and end of several time periods in Joda. The little devil on my left shoulder says thats the way to go... but I dont believe him. Could anybody with some joda experience take a brief look and tell me that the little guy is right? (It will be only… >>> More
Get non-overlapping dates ranges for prices history data

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello, Let's assume that I have the following table: CREATE TABLE [dbo].[PricesHist]( [Product] varchar NOT NULL, [Price] [float] NOT NULL, [StartDate] [datetime] NOT NULL, [EndDate] [datetime] NOT NULL ) INSERT [dbo].[PricesHist] ([Product], [Price], [StartDate], [EndDate]) VALUES (N'Apples'… >>> More
DateTime.MinValue vs new DateTime() in C#

as seen on Stack Overflow - Search for 'Stack Overflow'
When getting SQL DateTime Resharper suggests to use new DateTime() when value is DBNull.Value. I've always used DateTime.MinValue. Which is the proper way? DateTime varData = sqlQueryResult["Data"] is DateTime ? (DateTime) sqlQueryResult["Data"] : new DateTime(); >>> More
SOLVED: Error 1 Ticks must be between DateTime.MinValue.Ticks and DateTime.MaxValue.Ticks

as seen on Dot net Slackers - Search for 'Dot net Slackers'
This is a simple looking error message that is deceptively hard to track down. Thankfully if you're having this problem then this article should get you back on track without spending hours scratching your head. Scenario It was time to update an existing website so after synchronising my copy of… >>> More
Converting Openfire IM datetime values in SQL Server to / from VARCHAR(15) and DATETIME data types

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
A client is using Openfire IM for their users, and would like some custom queries to audit user conversations (which are stored by Openfire in tables in the SQL Server database). Because Openfire supports multiple database servers and multiple platforms, the designers chose to store all date/time… >>> More