diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/storage.sgml | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/doc/src/sgml/storage.sgml b/doc/src/sgml/storage.sgml index c20b2ebfe1b..8a2e7929e62 100644 --- a/doc/src/sgml/storage.sgml +++ b/doc/src/sgml/storage.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.14 2007/01/31 20:56:19 momjian Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/storage.sgml,v 1.15 2007/03/02 00:48:44 tgl Exp $ --> <chapter id="storage"> @@ -427,8 +427,8 @@ data. Empty in ordinary tables.</entry> The first 20 bytes of each page consists of a page header (PageHeaderData). Its format is detailed in <xref linkend="pageheaderdata-table">. The first two fields track the most - recent WAL entry related to this page. They are followed by three 2-byte - integer fields + recent WAL entry related to this page. Next is a 2-byte field + containing flag bits. This is followed by three 2-byte integer fields (<structfield>pd_lower</structfield>, <structfield>pd_upper</structfield>, and <structfield>pd_special</structfield>). These contain byte offsets from the page start to the start @@ -437,12 +437,13 @@ data. Empty in ordinary tables.</entry> The last 2 bytes of the page header, <structfield>pd_pagesize_version</structfield>, store both the page size and a version indicator. Beginning with - <productname>PostgreSQL</productname> 8.1 the version number is 3; + <productname>PostgreSQL</productname> 8.3 the version number is 4; + <productname>PostgreSQL</productname> 8.1 and 8.2 used version number 3; <productname>PostgreSQL</productname> 8.0 used version number 2; <productname>PostgreSQL</productname> 7.3 and 7.4 used version number 1; prior releases used version number 0. - (The basic page layout and header format has not changed in these versions, - but the layout of heap row headers has.) The page size + (The basic page layout and header format has not changed in most of these + versions, but the layout of heap row headers has.) The page size is basically only present as a cross-check; there is no support for having more than one page size in an installation. @@ -470,9 +471,15 @@ data. Empty in ordinary tables.</entry> </row> <row> <entry>pd_tli</entry> - <entry>TimeLineID</entry> - <entry>4 bytes</entry> - <entry>TLI of last change</entry> + <entry>uint16</entry> + <entry>2 bytes</entry> + <entry>TimeLineID of last change (only its lowest 16 bits)</entry> + </row> + <row> + <entry>pd_flags</entry> + <entry>uint16</entry> + <entry>2 bytes</entry> + <entry>Flag bits</entry> </row> <row> <entry>pd_lower</entry> |