r.alter( F i ,…; F’ i ,… )

Read(155) Label: record, alter, field,

Description:

Alter fields of a record.

Syntax:

r.alter(Fi,…;F’i,…)

Note:

The function alters fields of record r in the order of Fi,…. If the to-be-altered fields are not specified, perform the modification according to the original order of fields; if field Fi does not exist in the record, add it as a new field. F’i is the to-be-deleted fields.

Parameter:

r

A record.

Fi

Field names.

F’i

Names of to-be-deleted fields.

Return value:

Record

Example:

 

A

 

1

=demo.query("select top 9 class,studentid,subject,score from scores")

Return a table sequence:

2

=A1(1)

Return the 1st record of table sequence A1:

3

=A2.alter(classname;CLASS)

Add classname field to A2’s record while deleting CLASS field:

4

=A2.alter(classname,STUDENTID,gender)

Add classname field and gender field to A2’s record according to the order classname,STUDENTID,gender; put the rest of the fields CLASS,SUBJECT,SCORE after them:

5

=A2.alter(;CLASS)

Delete CLASS field from A2’s record: