Re: Which is faster when deleting rows? In() or Separate Delete stmts?

2007-11-03 Thread Baron Schwartz
Hi mos wrote: If I have a large table with 20 million rows, is it going to be faster to use one delete statement like: delete from mytable where rcdid in(20,300,423, 9) to delete 10-100 random records using the primary index "RcdId" or should I use separate delete statements for eac

Which is faster when deleting rows? In() or Separate Delete stmts?

2007-11-03 Thread mos
If I have a large table with 20 million rows, is it going to be faster to use one delete statement like: delete from mytable where rcdid in(20,300,423, 9) to delete 10-100 random records using the primary index "RcdId" or should I use separate delete statements for each RcdId as in:

Re: Static or Dynamic rows -- which is faster?

2002-02-13 Thread Keith C. Ivey
On 11 Feb 2002, at 18:27, Jeremy Zawodny wrote: > Nope, not for MyISAM it hasn't changed. With fixed rows, tables can > be checked, repaired, and accessed more quickly. If you know the row > size, you know how to get to row 500,123 quickly. It's just > multiplication. But if the row sizes are

Static or Dynamic rows -- which is faster?

2002-02-12 Thread David Felio
Whoops, originally sent this to just Heikki. > On Monday, February 11, 2002, at 12:12 PM, Heikki Tuuri wrote: > >> for InnoDB 'dynamic rows', that is, rows where you define char columns as >> VARCHAR, are faster because tables and indexes fit in smaller space. > > Is there reasoning specific to

Re: Static or Dynamic rows -- which is faster?

2002-02-12 Thread Heikki Tuuri
Eric, for InnoDB 'dynamic rows', that is, rows where you define char columns as VARCHAR, are faster because tables and indexes fit in smaller space. Only in some rare cases where you want to avoid fragmentation caused by updates which change a column length, a fixed-length CHAR(...) column can b

Static or Dynamic rows -- which is faster?

2002-02-12 Thread Eric Mayers
I have a large data set (15 mil rows) consisting of a datetime column and a char(255) column. I seem to recall seeing something about performance benefits for using static length rows with MyISAM tables, and I've heard some argument for using dynamic length rows (e.g., use varchar rather than cha

Re: Static or Dynamic rows -- which is faster?

2002-02-12 Thread Heikki Tuuri
Hi! -Original Message- From: David Felio <[EMAIL PROTECTED]> To: Heikki Tuuri <[EMAIL PROTECTED]> Date: Tuesday, February 12, 2002 12:47 AM Subject: Re: Static or Dynamic rows -- which is faster? >On Monday, February 11, 2002, at 12:12 PM, Heikki Tuuri wrote: > >

Re: Which is Faster

2002-02-12 Thread DL Neil
Dear Hayan, > Which of the following SQL queries is faster and better > "select thefield from thetable group by thetable" > Or > "select distinct thefield from thetable"? > and WHY? =if you use the MySQL command line to issue a query, a summary report follows any output giving number of rows a

Re: Static or Dynamic rows -- which is faster?

2002-02-11 Thread Jeremy Zawodny
On Mon, Feb 11, 2002 at 04:48:10PM -0600, David Felio wrote: > Whoops, originally sent this to just Heikki. > > On Monday, February 11, 2002, at 12:12 PM, Heikki Tuuri wrote: > >> for InnoDB 'dynamic rows', that is, rows where you define char columns as >> VARCHAR, are faster because tables and

Re: Which is Faster

2002-02-05 Thread BD
At 04:21 AM 2/5/2002 , you wrote: >Dear all, >Which of the following SQL queries is faster and better >"select thefield from thetable group by thetable" >Or >"select distinct thefield from thetable"? >and WHY? > >Best Regards >Hayan Hayan, I believe the "Select Distinct.." gets translate

Re: Which is Faster

2002-02-05 Thread DL Neil
Dear Hayan, > Which of the following SQL queries is faster and better > "select thefield from thetable group by thetable" > Or > "select distinct thefield from thetable"? > and WHY? =if you use the MySQL command line to issue a query, a summary report follows any output giving number of rows a

Which is Faster

2002-02-05 Thread Hayan Al Mamoun
Dear all, Which of the following SQL queries is faster and better "select thefield from thetable group by thetable" Or "select distinct thefield from thetable"? and WHY? Best Regards Hayan Get your own "800" number Voicemail, fax, email, and a l

Re: Which is faster VarChar(255) or Text?

2002-01-27 Thread Jeremy Zawodny
On Fri, Jan 25, 2002 at 09:42:07AM -0600, BD wrote: > > Jeremy, > > Thanks, I hadn't thought of TinyText. With flat file type > databases that I used to use, if I put something in a memo field, it > takes longer to retrieve the data because it is stored in a separate > physical file. Th

RE: Which is faster VarChar(255) or Text?

2002-01-25 Thread Johnny Withers
ED] Subject: Re: Which is faster VarChar(255) or Text? At 02:31 AM 1/25/2002 , you wrote: >On Thu, Jan 24, 2002 at 05:27:18PM -0600, BD wrote: > > > I will be putting variable length text into a field (up to 255 > > characters but typically around 60 characters) and wonder what makes

Re: Which is faster VarChar(255) or Text?

2002-01-25 Thread BD
At 02:31 AM 1/25/2002 , you wrote: >On Thu, Jan 24, 2002 at 05:27:18PM -0600, BD wrote: > > > I will be putting variable length text into a field (up to 255 > > characters but typically around 60 characters) and wonder what makes > > for faster retrieval? Or does it matter? A field defined as > >

Re: Which is faster VarChar(255) or Text?

2002-01-25 Thread Jeremy Zawodny
On Thu, Jan 24, 2002 at 05:27:18PM -0600, BD wrote: > I will be putting variable length text into a field (up to 255 > characters but typically around 60 characters) and wonder what makes > for faster retrieval? Or does it matter? A field defined as > Varchar(255) or Text? Do you mean VARCHAR(25

Which is faster VarChar(255) or Text?

2002-01-24 Thread BD
I will be putting variable length text into a field (up to 255 characters but typically around 60 characters) and wonder what makes for faster retrieval? Or does it matter? A field defined as Varchar(255) or Text? It is unlikely this field will be used for searching and it will not be indexed