Description:
Send records in a channel that can’t meet the given condition into another channel.
Syntax:
ch.select(x,ch’)
Note:
The function calculates expression x against each of the records in channel ch, and sends those records over which the value of x is false into channel ch’.
Parameter:
ch |
Channel |
x |
A Boolean expression |
ch’ |
Channel |
Return value:
Channel
Example:
|
A |
|
1 |
=demo.cursor("select EID,NAME,SALARY from EMPLOYEE " ) |
|
2 |
=channel() |
Create a channel. |
3 |
=channel() |
Create a channel. |
4 |
=A1.push(A2) |
Push data in A1’s cursor into A2’s channel. |
5 |
=A2.select(EID<5,A3) |
Push records in A2’s channel that can’t meet the condition EID<5 into A3’s channel. |
6 |
=A2.fetch() |
Attach ch.fetch() function that gets the final result set to A2’s channel to fetch and store the existing data in A2’s channel. |
7 |
=A3.fetch() |
Attach ch.fetch() function that gets the final result set to A3’s channel to fetch and store the existing data in A3’s channel. |
8 |
=A1.skip() |
It is when fetching data from A1’s cursor begins that data in the cursor is truly pushed to the channel and computations start. |
9 |
=A2.result() |
Get result of the computation in channel A2. |
10 |
=A3.result() |
Get result of the computation in channel A3. |