Constrain drillholes
This function allows you to restrict the data to be processed by defining constraints which will be applied to the data before the drillholes are displayed.
To run this function: Choose Database > Display > Add new constraint, or...
- In the Function Chooser, type CONSTRAIN DRILLHOLES, and press ENTER.
Enter collar constraints to specify the conditions which holes must meet to be considered inside the constraint. For example, entering Y > 7400 will restrict the set of holes to holes with a collar y value greater than 7400. Only these holes will be displayed when you display drillholes.
Each time CONSTRAIN DRILLHOLES is used, the constraint is added to the constraint stack. All constraints on the stack are added together to determine which drillholes from the database are displayed.
Fields on the Define Query Constraints form
| Field | Description |
|---|---|
| Table name | Read-only. The name of the table you opened is displayed at the top of the form. Take special note of the table name because it shows you which of the database tables the constraints will be applied to. |
| Field name | The name of the field on which you want to impose a constraint. If you leave Field name blank, all records in the table are selected. |
| Operand |
The mathematical operation that defines the constraint. The operands are:
|
| Constraint Value |
The value for the constraint. Press TAB to add an additional row, or right-click in the left column to add or remove constraint rows. When you have multiple constraint rows, Surpac returns only the records that pass all the constraints. However, you can use the hole_id field and the = operator to return records that pass only one of the constraints. In that situation, an OR operator is used between the constraints. For example, the following constraint would return two records:
Examples: For a surveying example, to select all the survey stations with a specific status, you could add a constraint: status = C The Constraint value for this constraint is C. To select drillholes or survey stations in a particular area, you could add three constraints:
To select all of the holes where the collar is on a specific bench of an open pit, you could enter two constraints similar to these:
|
| Load |
Loads a constraint from the .dbc file you choose. |
| Save | Saves the constraint to a .dbc file so you can reload it later. |
Note: Normally, a set of constraints is suitable for only the table on which it was created, or for tables that have the same or a very similar structure.Output
The drillholes that pass the new constrain combination are displayed in Graphics.