I advocate the following: - Enable specification of TOAST policy on a per column basis
As a first step, then: - Enable vertical partitioning of tables using per-column specification of storage policy. - Luke On 3/21/07 1:12 PM, "Bruce Momjian" <[EMAIL PROTECTED]> wrote: > > Is this a TODO? > > --------------------------------------------------------------------------- > > Jan Wieck wrote: >> On 3/21/2007 2:05 PM, Tom Lane wrote: >>> Chris Browne <[EMAIL PROTECTED]> writes: >>>> #define TOAST_DENOMINATOR 17 >>>> /* Use this as the divisor; current default behaviour falls from >>>> TOAST_DENOMINATOR = 4 */ >>> >>>> #define TOAST_TUPLE_THRESHOLD^I\ >>>> ^IMAXALIGN_DOWN((BLCKSZ - \ >>>> ^I^I^I^I MAXALIGN(sizeof(PageHeaderData) + 3 * sizeof(ItemIdData))) \ >>>> ^I^I^I^I / TOAST_DENOMINATOR) >>> >>> Given that you are quoting code that was demonstrably broken since the >>> original coding of TOAST up till a month or two back, "it passes >>> regression" is not adequate proof of "it's right". In fact I think >>> it's not right; you have not got the roundoff condition straight. >>> >>>> 4. A different mechanism would be to add a fifth storage column >>>> strategy (the present four are PLAIN, EXTENDED, EXTERNAL, MAIN), let's >>>> say, TOAST. >> >> FORCE_COMPRESSION, FORCE_EXTERNAL and FORCE_EXTERNAL_UNCOMPRESSED. >> >>> >>> Anything along this line would require invoking the toaster on every >>> single tuple, since we'd always have to crawl through all the columns >>> to see if toasting was supposed to happen. No thanks. >> >> Not necessarily. A flag in Relation telling if the table has any column >> marked like that could be set while constructing the relcache entry. >> >>> >>>> Which of these sounds preferable? >>> >>> It's a bit late in the cycle to be proposing any of these for 8.3. >> >> Certainly. >> >> >> Jan >> >> -- >> #======================================================================# >> # It's easier to get forgiveness for being wrong than for being right. # >> # Let's break this rule - forgive me. # >> #================================================== [EMAIL PROTECTED] # >> >> ---------------------------(end of broadcast)--------------------------- >> TIP 2: Don't 'kill -9' the postmaster ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
