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- Generic search/Exact-match search
- Space characters at the end of item
- Performing a search on a composite key
- Search on an array item
- Search and filter
HSeek (Function) In french: HRecherche
 Not available with this kind of connection
Positions on the first record of the data file whose value for a specific item is greater than or equal to a search value (generic search by default). The record is not read. To read the record, use HReadSeek. The number of the current record is modified only when it is returned by HRecNum. For functions handling the current record number by default (functions HDelete, HRead, HModify, ...), the value of this number is not updated: you must use the HRecNum() function. For example: do not:
but
HDelete(Client, HRecNum())
Read from smallest to largest browse item value (see notes for details). Attention: Record loaded into memory is not modified. HFSQL variables (e. g. Customer.Name, or the Name item of the Customer data file) are not updated. In most cases, HSeek sets the position in the data file to loop through the records that match a condition. HNext is used to position on the next record corresponding to the condition. Several cases may occur after the call to HSeek: - a Record corresponding to the condition has been found: function HFound returns True
- the data file is empty or there is no record corresponding to the condition: function HOut returns True
Remarks: - By default, HSeekFirst and HSeekLast are used to perform an exact-match search.
- By default, HSeek performs a generic search.
HSeek(Client, Nom, "Dupond" + Charact(0))
HSeek(Client, Nom, Complete("Dupond", 30))
Syntax
<Result> = HSeek(<Data file> , <Key item> , <Search value> [, <Options>])
<Result>: Boolean - True if the position was set,
- False in the event of an error (blocking, etc.): the Record is not played. This problem can be caused by:
- or a positioning problem (empty data file, etc.): function HFound returns False and function HError returns 0.
- an error: HError returns an integer other than 0. HErrorInfo returns more details.
<Data file>: Character string Name of the HFSQL data file used. <Key item>: Character string Name of key item on which the search will be performed. <Search value>: Type corresponding to the value Value of the sought item. <Options>: Optional constant (or combination of constants) Configures:- the lock mode applied to the sought record.
- the type of iteration
- the type of search performed.
| | | hIdentical | Exact-match search (see the Notes).
A generic search is performed by default (parameter not specified). | | hKeepFilter | The filter set by HFilter will be taken into account, even if the search key is not optimized for the filter. Reminder: HFilter returns the optimized search key for the filter.
Warning: in this case, on large data files, performance problems may occur..
| | hLimitParsing | The iteration will stop when the last searched value is found. The current record will correspond to the record found. In this case, HFound returns False and HOut returns True.
This constant is used to optimize the speed in Client/Server mode. | | hLockNo | No blocking: the Record can be played back or modified by another application during playback. | | hLockReadWrite | Read/write lock: the record being read cannot be read or modified by another application.
| | hLockWrite | Write lock: the record currently read can be read by another application but it cannot be modified by another application. |
Remarks Generic search/Exact-match search A generic search or an exact-match search will be performed according to <Sought value>. - Generic search: searches for all records beginning with the specified value
To perform a generic search, the desired value must be specified in <Sought value>. - Case of exact-match search In the case of an identical search: searches for all records corresponding exactly to the specified value.
To perform an exact-match search, the size of the search argument must be exactly the same as the size of the key. The search argument must be filled with "space" characters for the text keys. To do so, use the Complete function.
Space characters at the end of item By default, when a record is read, trailing spaces in text fields are not removed from variables associated with the data file. In order for the space characters to be deleted, use WithSpace. Performing a search on a composite key Several methods can be used to perform a search on a composite key: Using a list of values
The following syntax is used to perform a search on a composite key: HSeek(<File name>, <Name of composite key>, ...
[<Search value of first element of composite key>,
<Search value of first element of composite key>, ...]) Example:
HSeek(Client, Nom_Prénom, ["MOULIN","Françoise"])
Search on an array item The search is performed on the first array element (element with index 1). To perform a search on the other array elements, use the filters or queries. Search and filter If a filter is enabled ( HFilter), this filter is taken into account during the search.
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