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- .\" XXX standard disclaimer belongs here....
- .\" $Header: /private/postgres/ref/postquel/RCS/addattr,v 1.6 1992/07/14 05:54:17 ptong Exp $
- .SP ADDATTR COMMANDS 6/14/90
- .XA 2 "Addattr"
- .uh NAME
- .lp
- addattr \*- add attributes to a class
- .uh SYNOPSIS
- .lp
- .(l
- \fBaddattr\fR \fB(\fR attname1 \fB=\fR type1 {\fB,\fR attname-i \fB=\fR type-i} \fB)\fR
- \fBto\fR classname{*}
- .)l
- .uh DESCRIPTION
- .lp
- The
- .b addattr
- command
- causes new attributes to be added to an existing class,
- .i classname .
- The new attributes and their types are specified
- in the same style and with the the same restrictions as in
- \fBcreate\fR(commands).
- .lp
- The new attributes will not be added to
- any classes which inherit attributes from
- .i classname ,
- unless the
- .q *
- is present.
- .lp
- The initial value of each added attribute for all instances is
- .q "null."
- .lp
- For efficiency reasons,
- default values for added attributes
- are not placed in existing instances of a class.
- If default values are desired,
- a subsequent
- \fBreplace\fR(commands) query should be run.
- .uh EXAMPLE
- .lp
- .ft C
- /* add the date of hire to the emp class */
-
- addattr (hiredate = abstime) to emp
- .ft
- .uh "SEE ALSO"
- .lp
- create(commands).
- .uh "BUGS"
- .lp
- "*" is not supported in Version \*(PV.
-