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Release 7.1

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Major changes in this release:

Write-ahead Log (WAL) - To maintain database consistency in case

of an operating system crash, previous releases of PostgreSQL have

forced all data modifications to disk before each transaction commit.

With WAL, only one log file must be flushed to disk, greatly improving

performance. If you have been using -F in previous releases to disable

disk flushes, you may want to consider discontinuing its use.

Write-ahead Log (WAL) - To maintain database consistency in

case of an operating system crash, previous releases of PostgreSQL

have forced all data modifications to disk before each transaction

commit. With WAL, only one log file must be flushed to disk, greatly

improving performance. If you have been using -F in previous releases

to disable disk flushes, you may want to consider discontinuing its

use.

TOAST - Previous releases had a compiled-in row length limit,

typically8k -32k. This limit made storage of long text fields

difficult. With TOAST, long rows of any length can be stored with good

performance.

typically8 -32 kB. This limit made storage of long text fields

difficult. With TOAST, long rows of any length can be stored with

goodperformance.

Outer Joins - We now support outer joins. The UNION/NOT IN

workaround for outer joins is no longer required. We use the SQL92

outer join syntax.

Function Manager - The previous C function manager did not handle NULLs properly,

nor did it support 64-bit CPU's (Alpha). The new function manager does. You can continue

using your old custom functions, but you may want to rewrite them in the future to use the

Function Manager - The previous C function manager did not

handle NULLs properly, nor did it support 64-bit CPU's (Alpha). The

new function manager does. You can continue using your old custom

functions, but you may want to rewrite them in the future to use the

new function manager call interface.

Complex Queries - A large number of complex queries that were

unsupported in previous releases now work. Many combinations of views,

aggregates, UNION, LIMIT, cursors, subqueries, and inherited tables

now work properly. Inherited tables are now accessed by default.

Subqueries in FROM are now supported.

unsupported in previous releases now work. Many combinations of

views,aggregates, UNION, LIMIT, cursors, subqueries, and inherited

tablesnow work properly. Inherited tables are now accessed by

default.Subqueries in FROM are now supported.

Migration to 7.1