file(fn:z,hs)
Description:
Generate a cluster file on one or more nodes.
Syntax:
file(fn:z,hs)
Note:
The function generates a cluster file on node or a sequence of nodes hs. Parameter z is zone table number. The function retrieves zone tables of composite table fn from different nodes when z is an integer sequence; z cannot be a two-level integer sequence.
Parameter:
|
fn |
A composite table file |
|
z |
Zone table number(s), which is an integer or an integer sequence |
|
hs |
A node or a sequence of nodes |
Option:
|
@w |
Enable a remote generation with parameter z and parameter hs have a one-one-one correspondence; and is equivalent to to(hs.len()) when parameter z is absent |
Return value:
A cluster file
Example:
Generate a cluster file:
|
|
A |
|
|
1 |
=file("emp.ctx",["192.168.31.165:8281"]) |
Generate a cluster file on A1’s node. |
|
2 |
=A1.open() |
Open a cluster table. |
|
3 |
=A2.memory() |
Generate an in-memory cluster table. |
|
4 |
=A2.close() |
Close the cluster table. |
Write to a composite table file remotely:
|
|
A |
|
|
1 |
=["192.168.126.1:8281","192.168.31.165:8281"] |
A sequence of nodes. |
|
2 |
=file@w("emp.ctx":to(2),A1) |
Write files to nodes; write 1.emp.ctx to node 192.168.126.1:8281 and 2.emp.xtx to node 192.168.31.165. |
|
3 |
=create(k1,v1).record([1,10,2,20,3,30,4,40,10,100]) |
Return a table sequence. |
|
4 |
=A2.create(#k1,v1;if(k1<4,1,2)) |
Generate a multizone composite table. |
|
5 |
=A4.append(A3.cursor()) |
Append A3’s data to A4’s multizone composite table. |
Retrieve zone tables from nodes to generate a cluster file:
|
|
A |
|
|
1 |
=["192.168.126.1:8281","192.168.31.165:8281"] |
Define a sequence of nodes. |
|
2 |
=file("emCp.ctx":[1,2],A1) |
Retrieve zone tables from nodes to generate a cluster file; 1.empCp.ctx. and 2.empCp.ctx can be stored in node 192.168.126.1 and node 192.168.31.165:8281 respectively, or both can exist in either node. |
|
3 |
=A2.open() |
Open A2’s cluster file. |
|
4 |
=A3.memory() |
Generate an in-memory cluster table from A3’s cluster table. |
|
5 |
=A4.dup() |
Generate a local in-memory table from an in-memory cluster table. |