Description:
Get the primary key value of a record.
Syntax:
r.key(Fi,…)
Note:
The function gets the primary key value of record r according to key Fi. If Fi is omitted, return the basic key values. If the key isn’t set for r, return null. If it is a one-field key, just return the single key value; and with a composite key, return a sequence of values.
Parameter:
|
r |
A record. |
|
Fi |
Key. |
Return value:
Record’s primary key
Example:
|
|
A |
|
|
1 |
=demo.query("select * from EMPLOYEE ") |
|
|
2 |
=A1(1).key() |
1; return null because A1 doesn’t set a key. |
|
3 |
=A1.keys(EID) |
Set EID field as the key. |
|
4 |
=A1(1).key() |
1; return the primary key value of the first record. |
|
5 |
=A1.keys(EID,DEPT) |
Set EID&DEPT fields as the key. |
|
6 |
=A1(1).key() |
[1,R&D]; the primary key value is a sequence because the key consist of two fields. |
|
7 |
=A1(1).key(DEPT) |
R&D; get the value of a specified key field. |
Related function: