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Diffstat (limited to 'src/man/alter_table.l')
| -rw-r--r-- | src/man/alter_table.l | 59 |
1 files changed, 49 insertions, 10 deletions
diff --git a/src/man/alter_table.l b/src/man/alter_table.l index 67f50de8942..81929ff5b30 100644 --- a/src/man/alter_table.l +++ b/src/man/alter_table.l @@ -1,25 +1,33 @@ .\" This is -*-nroff-*- .\" XXX standard disclaimer belongs here.... -.\" $Header: /cvsroot/pgsql/src/man/Attic/alter_table.l,v 1.4 1998/01/11 22:17:04 momjian Exp $ +.\" $Header: /cvsroot/pgsql/src/man/Attic/alter_table.l,v 1.5 1998/03/31 04:44:19 momjian Exp $ .TH "ALTER TABLE" SQL 09/25/97 PostgreSQL .SH NAME -alter table - add attributes to a class +alter table - add attributes to a class, or rename an attribute or class .SH SYNOPSIS .nf \fBalter table\fR classname [ * ] \fBadd\fR [ \fBcolumn\fR ] attname type -.fi -.nf \fBalter table\fR classname [ * ] \fBadd\fR \fB(\fR attname type \fB)\fR +\fBalter table\fR classname1 + \fBrename to\fR classname2 + +\fBalter table\fR classname1 [\fB*\fR] + \fBrename [column]\fR attname1 \fBto\fR attname2 .fi + .SH DESCRIPTION The .BR "alter table" -command -causes a new attribute to be added to an existing class, -.IR classname . +command causes a new attribute to be added to an existing class, +.IR classname , +or the name of a class or attribute to change +without changing any of the data contained in the affected class. +Thus, the class or attribute will remain of the same type and size +after this command is executed. +.PP The new attributes and their types are specified in the same style and with the the same restrictions as in .IR "create table" (l). @@ -33,7 +41,9 @@ attribute will not be added to any of the subclasses.) This should be done when adding an attribute to a superclass. If it is not, queries on the inheritance hierarchy such as .nf -select * from super* s + + select * from super* s + .fi will not work because the subclasses will be missing an attribute found in the superclass. @@ -45,6 +55,24 @@ desired, a subsequent .IR update (l) query should be run. .PP +In order to rename an attribute in each class in an entire inheritance +hierarchy, use the +.IR classname +of the superclass and append a \*(lq*\*(rq. (By default, the attribute +will not be renamed in any of the subclasses.) This should +.BR always +be done when changing an attribute name in a superclass. If it is +not, queries on the inheritance hierarchy such as +.nf +select * from super* s +.fi +will not work because the subclasses will be (in effect) missing an +attribute found in the superclass. +.PP +You must own the class being modified in order to rename it or part of +its schema. Renaming any part of the schema of a system catalog is +not permitted. +.PP You must own the class in order to change its schema. .SH EXAMPLE .nf @@ -52,14 +80,25 @@ You must own the class in order to change its schema. -- add the date of hire to the emp class -- alter table emp add column hiredate abstime -.fi -.nf -- -- add a health-care number to all persons -- (including employees, students, ...) -- alter table person * add column health_care_id int4 +-- +-- change the emp class to personnel +-- +alter table emp rename to personnel +-- +-- change the sports attribute to hobbies +-- +alter table emp rename column sports to hobbies +-- +-- make a change to an inherited attribute +-- +alter table person * rename column last_name to family_name .fi .SH "SEE ALSO" create table (l), update (l). + |