de Melo Junior
[mailto:[EMAIL PROTECTED]]
Sent: Friday, May 10, 2002 3:41 PM
To: MYSQL
Subject: Length Limit
Hi,
Using the C API, does the sql parameter in the mysql_query function a length
limit?
Thank u very much,
Edilson.
Edilson Vasconcelos de Melo Junior
www.jrsoftwares.com.br
[EMAIL PROTE
Hi,
Using the C API, does the sql parameter in the mysql_query function a length
limit?
Thank u very much,
Edilson.
Edilson Vasconcelos de Melo Junior
www.jrsoftwares.com.br
[EMAIL PROTECTED]
Fone: (19) 3256-3577
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Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system
Steve Meyers wrote:
> In a previous message, I failed to mention one of the main reasons you
> would NOT want to use a 500-character primary key. MySQL uses a key
> buffer to keep as much index information in memory as possible. The
> longer the key, the less info it can keep in memory, and
In the last episode (Oct 23), Jeremy Zawodny said:
> On Mon, Oct 22, 2001 at 11:42:23AM -0600, Steve Meyers wrote:
> > If you use a good 64-bit hash, I doubt you'll run into any
> > uniqueness problems. MySQL will support that as a 64-bit BIGINT.
> > You especially should not have any problems if
On 23-Oct-2001 Steve Meyers wrote:
>> > At a previous job, we tested a 32-bit hash function by running it
>> > against hundreds of thousands of unique URL's stored in our
>> > database. We found one collision. A 64-bit hash is billions of
>> > times better (4 billion, to be exact).
>>
>> Good
> I am not understanding why having a hash and the full url in the
> database would not take care of the collisions. Even if you had
> 10 collisions for a 16 bit hash (say), if your query was:
> SELECT ... WHERE hash=thehashvalue AND url='theurl' you would get
> very fast lookups on the hash a
Hi!
I changed now ha_innobase.h so that InnoDB allows
keys up to 7000 bytes in length. The change will be
in MySQL-3.23.44 and 4.0.1.
Regards,
Heikki
http://www.innodb.com
>Steve Meyers wrote:
>
>> > > At a previous job, we tested a 32-bit hash function by running it
>> > > against hundreds of
Steve Meyers wrote:
> > > At a previous job, we tested a 32-bit hash function by running it
> > > against hundreds of thousands of unique URL's stored in our
> > > database. We found one collision. A 64-bit hash is billions of
> > > times better (4 billion, to be exact).
> >
> > Good to know.
> > At a previous job, we tested a 32-bit hash function by running it
> > against hundreds of thousands of unique URL's stored in our
> > database. We found one collision. A 64-bit hash is billions of
> > times better (4 billion, to be exact).
>
> Good to know. I wonder how many collisions I'd
> > At a previous job, we tested a 32-bit hash function by running it
> > against hundreds of thousands of unique URL's stored in our
> > database. We found one collision. A 64-bit hash is billions of
> > times better (4 billion, to be exact).
>
> Good to know. I wonder how many collisions I'd
On Mon, Oct 22, 2001 at 11:42:23AM -0600, Steve Meyers wrote:
>
> If you use a good 64-bit hash, I doubt you'll run into any
> uniqueness problems. MySQL will support that as a 64-bit BIGINT.
> You especially should not have any problems if you hash each column,
> then do the primary key across
> > The problem is that he has it as a primary key, so he wants it to be
>
> > unique as well as indexed. The best solution (and MUCH MUCH MUCH
>
> > more efficient) would be to hash each of the four columns, and create
> > a primary key on that. Integer keys are much faster and memory-
>
Steve Meyers wrote:
> The problem is that he has it as a primary key, so he wants it to be
> unique as well as indexed. The best solution (and MUCH MUCH MUCH
> more efficient) would be to hash each of the four columns, and create
> a primary key on that. Integer keys are much faster and me
keys.
Steve Meyers
> -Original Message-
> From: Chris Bolt [mailto:[EMAIL PROTECTED]]
> Sent: Saturday, October 20, 2001 8:31 PM
> To: [EMAIL PROTECTED]
> Subject: RE: Length limit of 500 on primary keys?
>
>
> > Is there a way to raise this limit? We have some
> Is there a way to raise this limit? We have some tables with columns that
> are VARCHAR(200), and need to make a primary key based on combinations of
> these columns (in some cases, upto 4 columns), and MySQL complains for all
> of these table definitions that "Specified key was too long. Max ke
Why is there a limit of 500 bytes on the primary key? (MySQL-Max-3.23.43 on
WinNT).
Is there a way to raise this limit? We have some tables with columns that
are VARCHAR(200), and need to make a primary key based on combinations of
these columns (in some cases, upto 4 columns), and MySQL compl
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