T.C

Read(609) Label: attached table column,

Description:

Get a specified column from an attached table.

Note:

Get the value of column C from attached table T. Its value will be recorded as nulls if the current record doesn’t have column C. If the value of column C corresponds to multiple records, only get the first record.

Parameters:

T

An attached table

C

A column of the attached table

Example:

 

A

 

1

=create(k1,v1).record([1,10,2,20,3,30,4,40,10,100])

Create a table sequence

2

=create(k1,k2,v2).record([1,1,"a",2,4,"c",2,8,"b"])

Create a table sequence

3

=file("D:/ckv.ctx")

 

4

=A3.create(#k1,v1)

Create the composite table’s base table

5

=A4.attach(table2,#k2,v2)

Add an attached table to the base table

6

=A4.append(A1.cursor())

Append data to the base table

7

=A5.append(A2.cursor())

Append data to the attached table

8

=A4.cursor(k1,v1,table2.k2,table2.v2).fetch()

Retrieve columns k1 and v1 from the composite table’s base table, and columns k2 and v2 from attached table table2; record values of k2 and v2 as empty if a record doesn’t have the two fields. Get the first record if there are multiple records in the attached table that correspond to one value