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Update for 6.5.3, including new INSTALL file and updated HISTORY.
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28
doc/FAQ
28
doc/FAQ
@@ -96,6 +96,7 @@
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4.21) My large-object operations get invalid large obj descriptor.
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Why?
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4.22) How do I create a column that will default to the current time?
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4.23) Why are my subqueries using IN so slow?
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Extending PostgreSQL
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@@ -198,8 +199,8 @@
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Unix/NT porting library. See pgsql/doc/README.NT in the distribution.
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There is also a web page at
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http://members.tripod.com/~kevlo/postgres/portNT.html. There is
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another port using U/Win at http://surya.wipro.com/uwin/ported.html.
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http://www.freebsd.org/~kevlo/postgres/portNT.html. There is another
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port using U/Win at http://surya.wipro.com/uwin/ported.html.
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1.5) Where can I get PostgreSQL?
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@@ -913,10 +914,27 @@ BYTEA bytea variable-length array of bytes
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but this makes the column default to the time of table creation, not
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the time of row insertion. Instead do:
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create table test (x int, modtime timestamp default text 'now');
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CREATE TABLE test (x int, modtime timestamp default now() );
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The casting of the value to text prevents the default value from being
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computed at table creation time, and delays it until insertion time.
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The calling of the function now() prevents the default value from
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being computed at table creation time, and delays it until insertion
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time. We believe this will not be a problem in post-6.5.* releases.
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4.23) Why are my subqueries using IN so slow?
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Currently, we join subqueries to outer queries by sequential scanning
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the result of the subquery for each row of the outer query. A
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workaround is to replace IN with EXISTS. For example, change:
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SELECT *
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FROM tab
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WHERE col1 IN (SELECT col2 FROM TAB2)
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to:
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SELECT *
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FROM tab
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WHERE EXISTS (SELECT col2 FROM TAB2 WHERE col1 = col2)
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We hope to fix this limitation in a future release.
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_________________________________________________________________
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Extending PostgreSQL
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