Greenhouse Gas Operator Definition
Comparison Operators
The Operator Definition and the Search Value fields allow you to enter specific search criteria to further refine the information that is being selected. The Operator Definition field allows you to specify the scope of the search value that you are entering under the Search Value option.
In database terms, the Search Options are really "comparison operators". What they do is compare the database column value against the search value that you've entered from the search. Based on the comparison, the database will either accept the row for processing or it will reject the row. Explanations for each operator are given below:
| OPERATOR | USAGE | RETRIEVAL EFFICIENCY |
|---|---|---|
| equals | The database will only return rows where the column value is equal to the search value. | Very Good |
| not equals | The database will only return rows where the column value is NOT equal to the search value. | Very Good |
| includes | The database will only return rows where the search value is contained within the column value. | Poor |
| excludes | The database will only return rows where the search value is NOT contained within the column value. | Poor |
| starts with | For Character fields only. The database will only return rows where the start of column value is equal to the search value. A comparison is done, character by character, up to the last character entered for the search value. | Very Good |
| not starts with | For Character fields only. The database will only return rows where the start of column value is NOT equal to the search value. A comparison is done, character by character, up to the last character entered for the search value. | Very Good |
| ends with | For Character fields only. The database will only return rows where the end of column value is equal to the search value. A comparison is done, character by character, up to the last character entered for the search value. | Very Good |
| not ends with | For Character fields only. The database will only return rows where the end of column value is NOT equal to the search value. A comparison is done, character by character, up to the last character entered for the search value. | Very Good |
| less than | For numerical fields only. The database will only return rows where the column value is less than the search value. | Very Good |
| less than or equal to | For numerical fields only. The database will only return rows where the column value is equal to or less than the search value. | Very Good |
| greater than | For numerical fields only. The database will only return rows where the column value is greater than the search value. | Very Good |
| greater than or equal to | For numerical fields only. The database will only return rows where the column value is equal to or greater than the search value. | Very Good |
| in | Instead of a single search value, the user can enter multiple search values, each separated by a comma. The database will only return rows where the column value is equal to one of the search values. | Good |