- Automatic management of composite keys
- Filter and filtered iteration
- Enabling/Disabling a filter
- Data file not in HFSQL format
<Source>.FilterIdentical (Function) In french: <Source>.FiltreIdentique
 Not available with this kind of connection
Defines and enables a filter used to find the exact value of a string item. This filter can be used on a data file, a view or a query. After its execution, the most common cases are as follows: - the filter cannot be created: <Source>.FilterIdentical returns an empty string (""). HError returns the error identifier.
- the filter is created: <Source>.FilterIdentical returns the optimized search key that will be used to loop through the data file, view or query.
// Select all the customers whose last name is Archambault
// and whose first name is Colin
SearchKey is string
SearchKey = Customer.FilterIdentical(LastNameFirstName, "Archambault", "Colin")
Customer.ReadFirst(SearchKey)
WHILE NOT Customer.Out()
Trace(Customer.CustomerName, Customer.City)
Customer.ReadNext(SearchKey)
END
// Disables the filter
Customer.DeactivateFilter()
Syntax
<Result> = <Source>.FilterIdentical(<Key item> , <Value for key component 1> [, <Value for key component 2> [... [, <Value for key component N>]]])
<Result>: Character string Browse item. Corresponds to:- the search key of data file if the filter is enabled.
- an empty string ("") if the filter cannot be implemented.
<Source>: Type corresponding to the specified source Name of the HFSQL data file, view or query used. <Key item>: Character string Name of key item onto which the filter will be applied. This item can be a simple key (string) or a composite key. Caution: this parameter must only contain letters, underlined characters or digits. Otherwise, the name must be enclosed in quotes. <Value for key component 1>: Type of each component of the search key Value sought for the first component of composite key.
The type of this parameter must correspond to the type of key item component on which the filter is defined. <Value for key component 2>: Type of each component of the search key Value sought for the second component of the composite key.
The type of this parameter must correspond to the type of key item component on which the filter is defined. <Value for key component N>: Type of each component of the search key Value sought for component N of composite key .
The type of this parameter must correspond to the type of key item component on which the filter is defined. Remarks Automatic management of composite keys <Source>.FilterIdentical automatically manages the filters on the simple keys and on the composite keys. Example: Using <Source>.FilterIdentical with a simple key:
Res = Customer.FilterIdentical(LastName, "Archambault")
// Select the customer whose last name is Archambault
Example: Using <Source>.FilterIdentical with a composite key
Res = Customer.FilterIdentical(LastNameFirstName, "Archambault", "Colin")
// Select all the customers whose last name is Archambault and
// whose first name is Colin
This line of code is equivalent to:
Customer.Filter(LastNameFirstName, ...
Customer.BuildKeyValue(LastNameFirstName, "Archambault", "Colin"), ...
Customer.BuildKeyValue(LastNameFirstName, "Archambault", "Colin")
Filter and filtered iteration After the call to <Source>.FilterIdentical, the iteration must be performed on the item returned by <Source>.FilterIdentical. The filter will be ignored if another item is used to loop through the data file. When a filter is defined and enabled on a data file (view or query), all records read correspond to the filter. If no other record corresponds to the filter during the iteration: - <Source>.Out returns True.
- the current record corresponds to the last record read with the filter.
For example: Enabling/Disabling a filter - <Source>.DeactivateFilter is used to disable a filter.
- <Source>.ActivateFilter is used to re-enable a filter.
- The filter is deleted when the data file (query or view) is closed (<Source>.Close or HOpenAnalysis for example).
- A single filter can exist at a given time on a data file (query or view). If <Source>.FilterIdentical is used several times, only the last filter will be taken into account: the previous filters will be deleted. Similarly, if several filters are used (HFilter* functions), only the last filter will be taken into account.
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