Features
PostgreSQL has most features present in large commercial
- DBMS's, like transactions, subselects, triggers, views, and
- sophisticated locking. We have some features they don't have,
- like user-defined types, inheritance, rules, and multi-version
- concurrency control to reduce lock contention. We don't have
- foreign key referential integrity or outer joins, but are
+ DBMS's, like transactions, subselects, triggers, views, foreign
+ key referential integrity, and sophisticated locking. We have
+ some features they don't have, like user-defined types,
+ inheritance, rules, and multi-version concurrency control to
+ reduce lock contention. We don't have outer joins, but are
working on them for our next release.
Performance
2.1) Are there ODBC drivers for PostgreSQL?
- There are two ODBC drivers available, PostODBC and OpenLink ODBC.
+ There are two ODBC drivers available, PsqlODBC and OpenLink ODBC.
- PostODBC is included in the distribution. More information about it
- can be gotten from: http://www.insightdist.com/psqlodbc
+ PsqlODBC is included in the distribution. More information about it
+ can be gotten from: ftp://ftp.postgresql.org/pub/odbc/index.html
OpenLink ODBC can be gotten from http://www.openlinksw.com. It works
with their standard ODBC client software so you'll have PostgreSQL
commercial-quality support, but a freeware version will always be
+ See also the ODBC chapter of the Programmer's Guide.
+
2.2) What tools are available for hooking PostgreSQL to Web pages?
A nice introduction to Database-backed Web pages can be seen at:
4.22) How do I create a column that will default to the current time?
- This way always works:
+ Use now():
CREATE TABLE test (x int, modtime timestamp default now() );
- In releases 7.0 and later, you may use:
- create table test (x int, modtime timestamp default 'now');
-
4.23) Why are my subqueries using IN so slow?
Currently, we join subqueries to outer queries by sequential scanning
PostgreSQL has most features present in large commercial DBMS's, like
-transactions, subselects, triggers, views, and sophisticated locking.
-We have some features they don't have, like user-defined types,
-inheritance, rules, and multi-version concurrency control to reduce lock
-contention. We don't have foreign key referential integrity or outer
+transactions, subselects, triggers, views, foreign key referential
+integrity, and sophisticated locking. We have some features they don't
+have, like user-defined types, inheritance, rules, and multi-version
+concurrency control to reduce lock contention. We don't have outer
joins, but are working on them for our next release.
Performance
2.1) Are there ODBC drivers for PostgreSQL?
-There are two ODBC drivers available, P
ostODBC and OpenLink ODBC.
+There are two ODBC drivers available, P
sqlODBC and OpenLink ODBC.
-PostODBC is included in the distribution. More information about it can
-
http://www.insightdist.com/psqlodbc
+PsqlODBC is included in the distribution. More information about it can
+
ftp://ftp.postgresql.org/pub/odbc/index.html
OpenLink ODBC can be gotten from
http://www.openlinksw.com. It works with their standard ODBC client