Global
Global
A globals ia a number that is intecrated in the project but is not nessccarelay assinged to a specifiche object. The global can be used for Excel calculations and therefor influence the projects outcome.
Type of globals
The main operation used in TQL is the query, which is performed with the declarative SELECT
statement or UPDATE
statement. A declarative statement tells the system which data is specifically required, after which the system will retrieve the data on it's 'own'. This is contrary to an imperative statement, where the system is told 'how' to obtain said data. A SELECT
statement retrieves data from a running Tygron project session. A UPDATE
statement changes data from a running Tygron project session. Queries using SELECT
statements have no persistent effect on the project session itself. Queries using the UPDATE
statement do have an effect om the project session itself. The UPDATE
statement is used in the Excel indicator calculations and the outcome of the calculation is redirected as output to update the key figures in the project.
Queries in TQL using the SELECT
statement allow the user to describe the desired data, leaving the Tygron Engine responsible for planning, optimizing, and performing the physical operations necessary to produce the desired result as output.
Queries using the UPDATE
statement allow the user to make use of the results of Excel calculations as an output in the Engine and in this way adapt the data in a project session.
When starting a query with the SELECT
statement, a result parameter must follow after the SELECT
keyword. Currently, one of the following result parameters can be selected:
Result Parameter | Description | Example |
---|---|---|
FLOORSIZE
|
Floor size of buildings. | SELECT_FLOORSIZE_WHERE_CATEGORY_IS_OFFICES
|
LOTSIZE
|
Lot size of buildings. | SELECT_LOTSIZE_WHERE_CATEGORY_IS_OFFICES
|
UNITS
|
Amount of housing units. | SELECT_UNITS_WHERE_CATEGORY_IS_SOCIAL
|
LANDSIZE
|
Amount of surface area. | SELECT_LANDSIZE_WHERE_BEHAVIOR_IS_GRASSLAND
|
DIKES
|
Surface space of constructed dikes or levees. | SELECT_DIKES_WHERE_ZONE_IS_1
|
ACTIVE
|
whether something is relevant in the project. | SELECT_ACTIVE_WHERE_ZONE_IS_1
|
NAME *
|
Name of selection as query result | SELECT_NAME_WHERE_CATEGORYMULT_IS_SELL_PRICE_M2
|
COLOR *
|
Color of selection as query result | SELECT_COLOR_WHERE_FUNCTION_IS_816
|
GRID_AVG
|
Average grid value per grid point | SELECT_GRIDAVG_WHERE_GRIDTYPE_IS_TRAFFIC_NOISE
|
* can be followed by one clause maximum
Comparison Predicate
The SELECT
and result parameter are followed by a WHERE
statement. The WHERE
statements contains a comparison predicate, which are logical propositions that restrict the information retrieved by the query. In other words, the WHERE
clause eliminates all information from the result set where the comparison predicate does not evaluate as being valid (Boolean = True).
Take for instance the following statement as example of a logical proposition:
- The Student is a Senior.
This statement excludes all students that are Junior, Sophomore or Freshman, as the outcome of the logical proposition would be 'False' in these cases.
The comparison predicate consists of 0 or more clauses, which consist of three parts;
- Clause Type
- Operator
- Value
Create a Global
In order to make it easier to construct queries, a tool has been developed to create queries in the editor, which can then be copied and used elsewhere. This tool is known as the Query Tool and more information can be found on its own page.
Global Uses
Globals are currently used to communicate with a Microsoft Excel spreadsheet, when using such a spreadsheet for a (custom) Excel Indicator.