Runs a view that was created beforehand (can be used to refresh the view data for example). If the view was created with the
<Source>.CreateView function using the
hVueDifférée constant, it is necessary to use the
<Source>.ExecuteView function to execute the view.
Reminder: a view corresponds to the image of a data file at a given time. A view is stored in memory, which insulates it from the modifications performed in the associated data file. A view can be handled like a standard HFSQL data file.
Versions 17 and later
New in version 17Versions 18 and later New in version 18 Versions 21 and later New in version 21 Remark: From version 19, HFSQL is the new name of HyperFileSQL.
// Runs the Customer34 view
Client34.ExecuteView()
Syntax
<Result> = <Source>.ExecuteView([<Selection condition>])
<Result>: Boolean
- True if the view was run,
- False otherwise. HError returns more details about the problem.
<Source>: Type of Source
Name of view to run. This name was defined by <Source>.CreateView.
<Selection condition>: Optional character string
- New selection condition for the view records (<Selection Condition> replaces the condition specified when creating the view). This selection condition can be a character string in Ansi or Unicode format.
- Empty string ("") to avoid modifying the selection condition.
Remarks
Selection condition
The general syntax of a condition has the following format:
"CustName>'Smith' and ZipCode=34 or ZipCode=32"
The supported operators depend on the type of items used in the condition:
| | |
| <> | Different | Valid for all types |
| > | Greater than | Valid for all types |
| >= | Greater than or equal to | Valid for all types |
| < | Less than | Valid for all types |
| <= | Less than or equal to | Valid for all types |
| = | Strictly equal to | Valid for all types |
| ~= | Almost equal to | Valid for string types only |
| ] | Contains | Valid for string types only |
| ]= | Starts with | Valid for string types only |
Notes about the selection condition:
- The constant strings must be enclosed in simple quotes.
- If an item name is used in the selection condition, it must only contain letters, numbers and underscore characters ("_"). If the item name contains other characters (apostrophe, etc.), the name of the item must be enclosed in double quotes.
For example: "e_mail@"]'fr' - Comparisons between strings are performed according to the ASCII value of the characters and not according to the lexicographic value ('a' > 'Z').
- The binary memos, the composite keys and the subscripted items cannot be part of a selection condition.
- If a <string constant> contains a simple quote (or a double quote), this simple quote (or double quote) must be preceded by a backslash character ( \ ).
- All the items of the main data file can be included in the condition (even the ones that are not items of the view).
- The condition is applied to each virtual record before it is included in the view. Therefore, you cannot specify several mutually excluding conditions for the same record (join). For example:
- "Date='1997' and Date='1996'" returns no result.
- "Date>='1996' and Date<='1997'" returns all the records found between 1996 and 1997.
- This selection condition can be a character string in Ansi or Unicode format.