dup()

Read(3512) Label: dup,

Here’s how to use dup() functions.

T.dup()

Description:

Join up a cluster in-memory table into a local in-memory table.

Syntax:

T.dup()

Note:

The function joins up cluster in-memory table T to generate a local in-memory table.

Parameter:

T

A cluster in-memory table

Return value:

An in-memory table

Example:

 

A

 

1

=file("D:/test0.ctx","169.254.121.62:8281")

Open a cluster file.

2

=A1.open()

Return a cluster table.

3

=A2.attach(table)

Retrieve cluster table table.

4

=A3.memory()

Generate a cluster memory table.

5

=A4.dup()

Join up the cluster in-memory table to return a local in-memory table.

T.dup(h)

Description:

Copy a local in-memory table onto nodes to create a duplicate cluster in-memory table.

Syntax:

T.dup(h)

Note:

The function copies local in-memory table T onto node or node sequence h to create a duplicate cluster in-memory table. The memory footprints will be cleaned up once T.close() is executed.

Parameter:

T

A local in-memory table

h

A node or a node sequence

Return value:

A duplicate cluster in-memory table

Example:

 

A

 

1

=demo.cursor("select EID,NAME,GENDER,SALARY from EMPLOYEE where EID<10")

 

2

=A1.memory()

Generate a local in-memory table.

3

=A2.dup("169.254.121.62:8281","192.168.31.165:8281")

Copy the local in-memory table into a duplicate cluster in-memory table.