Is the base of a Select a number or a string?
By default — this is a string in which the row id number is recorded.
Which parameter of the selectRowListForTree function is used to change the base to another field?
Since the base is a string, it can be changed to another base. For example, if unique articles are used for correspondences in your solution.
In this case, an additional parameter bfield (from base field) is used in selectRowListForSelect. It specifies which field will be the basis for the select.
=: selectRowListForSelect(table: 'table'; field: 'name'; bfield: 'uuid')
What happens if the identifier in the source table is not unique?
To ensure everything works correctly, the bases in the source table must be unique. If this is not the case, the display for identical bfield values will be taken randomly.
If values have already been put in the Select field, then when you change the ID, they will automatically be changed to the new values?
No — you will see crossed-out values.
Can the code glue together a select from multiple tables?
Yes. Usually, this is done only for bfield selects, because id from two different tables can be duplicated.
Selects are concatenated as lists using the listAdd function:
=: listAdd(list: $s1; list: $s2)
s1: selectRowListForSelect(table: 'table_1'; field: 'name'; bfield: 'uuid_1')
s2: selectRowListForSelect(table: 'table_1'; field: 'name'; bfield: 'uuid_2')