Key Value Table
An object that maps keys to values. It works in the following way: you choose one column of the database table as the key column and tell what column contains values that should be mapped to this key. A map cannot contain duplicate keys; each key can map to at most one value.
Key-Value mappings are loaded from database via
execute()
function or on first call of any data-retrieving function.
The value mapping for given key can be obtained using
get(Object)
function call.
Creating a mapping object
To add key-value object
- Drag the
Key Value Table
element from the
Connectivity
stencil of the
Palette
onto the graphical diagram.
- In the
Properties
view, modify the
Name
of the element. This name will be used to identify and access this object.
- Specify the database this object will work with. Type the name of the AnyLogic database in the
Database
edit box.
- In the
Table
edit box, type the name of the database table this object will access.
- Type the name of the table column that contains keys in the
Key Column
field.
- Specify the type of the keys in the
Key Column Type
drop-down list.
- In the
Value Column
field, type the name of the column that contains values you want to map with keys .
- Specify the type of the value column in the
Value Column Type
drop-down list.
Working with key-value table via API
You work with created mapping object using the corresponding API of the
KeyValueTable
class.
The most frequently needed function is the following:
V get(K key)
- The function returns the value to which the specified key is mapped, or null if this KeyValueTable contains no mapping for the key.