diff --git a/doc/FAQ b/doc/FAQ index c092e10b9c..3c35b3c2ec 100644 --- a/doc/FAQ +++ b/doc/FAQ @@ -1,7 +1,7 @@ Frequently Asked Questions (FAQ) for PostgreSQL - Last updated: Mon Jan 31 20:35:58 EST 2005 + Last updated: Mon Jan 31 20:41:21 EST 2005 Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) @@ -51,7 +51,7 @@ 4.1) How do I SELECT only the first few rows of a query? A random row? 4.2) How do I find out what tables, indexes, databases, and users are defined? How do I see the queries used by psql to display them? - 4.3) How do you remove a column from a table, or change its data type? + 4.3) How do you change a column's data type? 4.4) What is the maximum size for a row, a table, and a database? 4.5) How much database disk space is required to store data from a typical text file? @@ -491,25 +491,16 @@ query to get information about the database. There are also system tables beginning with pg_ that describe these - too. Use psql -l will list all databases. + too. + + Use psql -l will list all databases. Also try the file pgsql/src/tutorial/syscat.source. It illustrates many of the SELECTs needed to get information from the database system tables. - 4.3) How do you remove a column from a table, or change its data type? + 4.3) How do you change a column's data type? - DROP COLUMN functionality was added in release 7.3 with ALTER TABLE - DROP COLUMN. In earlier versions, you can do this: - BEGIN; - LOCK TABLE old_table; - 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; - COMMIT; - Changing the data type of a column can be done easily in 8.0 and later with ALTER TABLE ALTER COLUMN TYPE. diff --git a/doc/src/FAQ/FAQ.html b/doc/src/FAQ/FAQ.html index 1385d59012..71fd857710 100644 --- a/doc/src/FAQ/FAQ.html +++ b/doc/src/FAQ/FAQ.html @@ -10,7 +10,7 @@ alink="#0000ff">
Last updated: Mon Jan 31 20:35:58 EST 2005
+Last updated: Mon Jan 31 20:41:21 EST 2005
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
@@ -74,8 +74,7 @@
4.2) How do I find out what tables, indexes,
databases, and users are defined? How do I see the queries used
by psql to display them?
- 4.3) How do you remove a column from a
- table, or change its data type?
+ 4.3) How do you change a column's data type?
4.4) What is the maximum size for a row, a
table, and a database?
4.5) How much database disk space is required
@@ -645,28 +644,15 @@
database.
There are also system tables beginning with pg_ that describe - these too. Use psql -l will list all databases.
+ these too. + +Use psql -l will list all databases.
Also try the file pgsql/src/tutorial/syscat.source. It illustrates many of the SELECTs needed to get information from the database system tables.
-DROP COLUMN functionality was added in release 7.3 - with ALTER TABLE DROP COLUMN. In earlier versions, - you can do this:
-- BEGIN; - LOCK TABLE old_table; - 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; - COMMIT; -+
Changing the data type of a column can be done easily in 8.0 and later with ALTER TABLE ALTER COLUMN TYPE.