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Posted by Jerry Stuckle on 10/12/47 11:39
frizzle wrote:
> Jerry Stuckle wrote:
>
>>frizzle wrote:
>>
>>>pjSoni wrote:
>>>
>>>
>>>>Hi
>>>>
>>>>Try to do like when admin enters article he should enter <SPLIT> tag
>>>
>>>>from where you want break with article so when you read from db try to
>>>
>>>>split from split tag.
>>>>
>>>>Regards,
>>>>Jatin
>>>
>>>
>>>Thanks all for the replies.
>>>I understand what bobzimuta and pjSoni are saying with the intro thing,
>>>but i need two different fields, so the intro in the fulltext can
>>>differ from just te intro.
>>>
>>>I think i'll go with Jerry's: SELECT COUNT(id) FROM texttable WHERE
>>>id=1;
>>>But the id of the fulltext would have to match the exact id of the
>>>record with intro and other info?
>>>Would it matter if i added LIMIT 1 to it, so the DB won't go on?
>>>
>>>How careful should i be asigning extra indexes? I read somewhere, that
>>>if i asign indexes to fields that aren't going te be updated a lot,
>>>it's not bad, otherwise it would take a lot of time ...
>>>
>>>And now i also have second thoughts about my field in the topic records
>>>with the number of replies.
>>>It goes against normalization, but i thought it would save a lot of
>>>calculating time ...
>>>
>>>Frizzle.
>>>
>>
>>Yes, it has to match the key of the other table. It would also the
>>primary key of that entry. Being a primary key, it would be unique.
>>
>>Also, if your use INNODB tables you can make it a foreign key
>>referencing the other table.
>>
>>You shouldn't need to add LIMIT 1 to the query because you have a unique
>>index on the field. MySQL should be able to fetch everything it needs
>>from the index (which, unlike the table, is in order).
>>
>>--
>>==================
>>Remove the "x" from my email address
>>Jerry Stuckle
>>JDS Computer Training Corp.
>>jstucklex@attglobal.net
>>==================
>
>
> Why is this unlike the table in order? Since both are probably created
> in the same instance. The Fulltext indexes have a bigger chance *not*
> to be in order, since they could be added later ...
>
> And what exactly do you mean with a foreign key ?
>
> Frizzle.
>
> (Thanks a lot for your effort to help me!)
>
First of all, check out foreign keys in the MySQL documentation:
http://dev.mysql.com/doc/refman/5.0/en/ansi-diff-foreign-keys.html
No, the table wouldn't necessarily be in order (your original one
wouldn't either - SQL is by default unordered). But the index built on
the primary key is always ordered (so the engine can do a quick binary
search of the index). Therefore, MySQL can determine whether a record
exists or not by searching the index and doesn't need to load the file
itself in the query I showed you.
But the advantage is you wouldn't have to read the full text data every
time you need to access the summary information. You only get the full
text when you request it.
Remember - MySQL reads the entire row, even if you only ask for part of
the data, because everything's in one file.
Also, if you have a request which requires a full table scan, having the
full text in a separate table improves the table scan (unless, of
course, you're searching the full text data).
--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================
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