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From:wangxu Date:April 12 2007 2:13pm
Subject:Re: Can I create a index on a column of Type datetime?
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Thank you,
what 's the meaning of "using a datetime field unless it's the last
field in the index."?


the below is the desc result;Should I create an index on
(source_url,create_date)?
for these two fields are to be often queried by.
+---------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+---------------+--------------+------+-----+---------+----------------+
| id | bigint(20) | NO | PRI | NULL | auto_increment |
| create_date | datetime | NO | | | |
| brand | varchar(255) | YES | | NULL | |
| category | varchar(255) | YES | | NULL | |
| description | text | YES | | NULL | |
| detailed_desc | text | YES | | NULL | |
| imageUrl | varchar(255) | YES | | NULL | |
| name | varchar(255) | YES | | NULL | |
| price | varchar(255) | YES | | NULL | |
| properties | text | YES | | NULL | |
| sku | varchar(255) | YES | | NULL | |
| source_url | varchar(255) | YES | | NULL | |
| link_path | varchar(255) | YES | | NULL | |
| site_name | varchar(255) | YES | MUL | NULL | |
| page_score | float | YES | | NULL | |
| tag | varchar(255) | YES | | NULL | |
| dumped | bit(1) | YES | | NULL | |
+---------------+--------------+------+-----+---------+----------------+


Brent Baisley wrote:
> You can create an index on just about any field. Just remember that
> the data in a datetime field is fairly unique, so it would do much
> good to create a compound index (2 or more fields) using a datetime
> field unless it's the last field in the index.
>
> ----- Original Message ----- From: "wangxu" <wangxu@stripped>
> To: <mysql@stripped>
> Sent: Wednesday, April 11, 2007 8:08 PM
> Subject: Can I create a index on a column of Type datetime?
>
>
>> I will very often do query like this:
>>
>> select * from mytable where create_date >='...' and create_date <='....'
>>
>> can I create a index on the column create_date?
>>
>> what is the best practise?
>>
>> Thanks,
>> shell.
>>
>>
>> -- 
>> MySQL General Mailing List
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>>
>
>
>

Thread
Can I create a index on a column of Type datetime?wangxu11 Apr
  • Re: Can I create a index on a column of Type datetime?Martijn Tonies11 Apr
    • Re: Can I create a index on a column of Type datetime?wangxu12 Apr
  • Re: Can I create a index on a column of Type datetime?Brent Baisley12 Apr
Re: Can I create a index on a column of Type datetime?wangxu12 Apr