cs.(x)

Read(2351) Label: cursor, expression,

Description:

Attach the action of computing expression to a cursor and return the original cursor.

Syntax:

cs.(x)

Note:

The function computes expression x on each member of the cursor and returns the original cursor.

This is a delayed function.

Parameter:

cs

A cursor

x

An expression that is generally a single field name or a legal expression composed of multiple field names; both can use ~ to reference the current record; can be omitted

Return value:

Cursor

Example:

 

A

 

1

=connect("demo").cursor("select top 5 EID,NAME,HIREDATE from EMPLOYEE where EID<10")

Return a cursor.

2

=A1.(age(HIREDATE))

Attach a computation to cursor A1 – compute the length of service according to HIERDATE, and return the original cursor.

3

=A1.fetch()

Fetch data from cursor A1 on which the attached computation is already executed (it would be better to fetch data in batches when data amount involved is huge):

4

=A1.reset()

Reset cursor A1 and move it back to the beginning.

5

=A1.(2*~+1)

Attach a computation to cursor A1 – compute length of service*2+1 and ~ references the current record, and return the original cursor.

6

=A1.fetch()

Fetch data from cursor A1 on which A5’s computation is already executed:

When parameter x is absent:

 

A

 

1

=demo.cursor("select top 3 DEPT,MANAGER from DEPARTMENT")

Return a cursor.

2

=A1.()

As parameter x is absent, no computation is performed on cursor A1 and the function returns the same cursor.

3

=A1.skip()

Get the number of records in cursor A1 and return 3.