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Update README, HISTORY, etc for beta release.

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Bruce Momjian
1997-09-14 02:09:10 +00:00
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@ -1,8 +1,8 @@
Frequently Asked Questions (FAQ) for PostgreSQL
Last updated: Thu Sep 4 01:32:22 EDT 1997
Version: 6.1.1
Last updated: Sat Sep 13 22:00:02 EDT 1997
Version: 6.2beta
Current maintainer: Bruce Momjian (maillist@candle.pha.pa.us)
@ -90,6 +90,7 @@ Questions answered:
3.21) What is the meaning of some of the terms used in Postgres?
3.22) What is Genetic Query Optimization?
3.23) How do you remove a column from a table?
3.24) How do SELECT only the first few rows of a query?
4) Questions about extending PostgreSQL
@ -514,24 +515,7 @@ Section 3: PostgreSQL Features
3.6) What is the exact difference between binary cursors and normal cursors?
Normal cursors return data back in ASCII format. Since data is stored
natively in binary format, the system must do a conversion to produce
the ASCII format. In addition, ASCII formats are often large in size
than binary format. Once the attributes come back in ASCII, often the
client application then has to convert it to a binary format to
manipulate it anyway.
Binary cursors give you back the data in the native binary
representation. Thus, binary cursors will tend to be a little faster
since there's less overhead of conversion.
However, ASCII is architectural neutral whereas binary representation
can differ between different machine architecture. Thus, if your
client machine uses a different representation than you server
machine, getting back attributes in binary format is probably not what
you want. Also, if your main purpose is displaying the data in ASCII,
then getting it back in ASCII will save you some effort on the client
side.
See the declare manual page for a description.
3.7) What is a R-tree index and what is it used for?
@ -590,24 +574,12 @@ Section 3: PostgreSQL Features
3.10) How do I do regular expression searches? case-insensitive regexp
searching?
PostgreSQL supports the SQL LIKE syntax as well as more general
regular expression searching with the ~ operator. The !~ is the
negated regexp operator. ~* and !~* are the case-insensitive regular
expression operators.
See the pgbuiltin manual page. Search for regular expression.
3.11) I experienced a server crash during a vacuum. How do I remove the lock
file?
If the server crashes during a vacuum command, chances are it will
leave a lock file hanging around. Attempts to re-run the vacuum
command result in
WARN:can't create lock file -- another vacuum cleaner running?
If you are sure that no vacuum is actually running, you can remove the
file called "pg_vlock" in your database directory (which is
$PGDATA/base/<dbName>)
See the vacuum manual page.
3.12) What is the difference between the various character types?
@ -638,10 +610,8 @@ BYTEA bytea variable-length array of bytes
3.14) How do I see how the query optimizer is evaluating my query?
Place the word 'EXPLAIN' at the beginning of the query, for example:
EXPLAIN SELECT * FROM table1 WHERE age = 23;
See the explain manual page.
3.15) How do I create a serial field?
Postgres does not allow the user to specifiy a user column as type
@ -683,6 +653,7 @@ BYTEA bytea variable-length array of bytes
The default configuration allows only connections from tcp/ip host
localhost. You need to add a host entry to the file pgsql/data/pg_hba.
See the hba_conf manual page.
3.18) How do I find out what indexes or operations are defined in the
database?
@ -769,11 +740,20 @@ BYTEA bytea variable-length array of bytes
We do not support ALTER TABLE DROP COLUMN, but do this:
SELECT ... # select all columns but the one you want to remove
SELECT ... -- select all columns but the one you want to remove
INTO TABLE new_table
FROM old_table;
DROP TABLE old_table;
ALTER TABLE new_table RENAME TO old_table;
3.23) How do SELECT only the first few rows of a query?
See the fetch manual page.
This only prevents all row results from being transfered to the
client. The entire query must be evaluated, even if you only want just
first few rows. Consider a query that has and ORDER BY. There is no
way to return any rows until the entire query is evaluated and sorted.
_________________________________________________________________
Section 4: Extending PostgreSQL
@ -819,4 +799,4 @@ Section 5: Bugs
You can also fill out the "bug-template" file and send it to:
* bugs@postgreSQL.org
This is the address of the developers mailing list.
This is the address of the developers mailing list.