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  • Read operation based on a key
  • Comparison between <Source>.Next and .ReadNext
  • Miscellaneous
  • Locks
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Stored procedures
Sets the position on the next data file record according to a browse item. The record is not read.
The number of the current record is modified only when it is returned by <Source>.RecNum. For the functions that handle the current record number (<Source>.Delete, <Source>.Read, <Source>.Modify, etc.), the value of this number is not updated: you must use <Source>.RecNum(). For example: not to do:
Customer.Delete()
but
Customer.Delete(Customer.RecNum())
Values in the browse item are read in ascending order (see Remarks for more details).
Caution: The record loaded in memory is not modified. The HFSQL variables (Customer.Name for example, which means the Name item of Customer file) are not updated.
In most cases, <Source>.Next sets the position in the data file to loop through the records that match a condition. <Source>.Next is used to position on the next record corresponding to the condition.
Several cases may occur after the call to <Source>.Next:
  • a record corresponding to the condition was found: <Source>.Found returns True
  • the data file is empty or there is no record corresponding to the condition: <Source>.Out returns True
Remarks:

Values in the browse item are read in ascending order (for more details, see the remarks).
Caution: The record loaded in memory is not modified. The HFSQL variables (for example Customer.Name, i.e. the Name item of the Customer file) are not updated.
Generally, <Source>.Next sets the position in the data file during a loop operation.
Several cases may occur after the call to <Source>.Next:
  • the data file is empty or no record corresponds to the filter (defined by <Source>.Filter): <Source>.Out returns True
  • the function tries to lock a record that is already locked in read-only: HErrorLock returns True and <Source>.Out returns True.
    Java Access by JDBC: Locks cannot be managed in databases accessed by JDBC.
Example
Customer.First(Name)
WHILE Customer.Out() = False
// Process the record
Customer.Next(Name)
END
Syntax
<Result> = <Source>.Hnext([<Search key item> [, <Options>]])
<Result>: Boolean
  • True if the position was set,
  • False if an error occurred. This problem can be caused by:
<Source>: Type corresponding to the specified source
Name of the HFSQL data file.
<Search key item>: Optional character string
Name of the key item used to loop through the data file. If this name is not specified, <Source>.Next will use the last browse item used on this data file by the last HFSQL management function (function starting with "H"). If this item does not exist, the best browse item is automatically used.
<Options>: Optional constant
Configures the lock and the management of duplicates performed on the record selected by <Source>.Next:
hDistinctIf there are any duplicates, sets the position on a single record of the duplicates. This parameter is taken into account only if the iteration is performed on a key item.
By default, all duplicates are iterated over.
OLE DBNative Connectors (Native Accesses) This constant is ignored.
hLockNoNo lock: the record can be read or modified by another application.
hLockReadWriteLock in read/write: the selected record cannot be read or modified by another application.
OLE DB Lock in write-only: the record currently read can be read by another application but it cannot be modified.
Operating mode equivalent to the one of hLockWrite.
hLockWriteLock in write mode: the selected record can be read by another application but it cannot be modified.
Java Access by JDBC: This parameter is ignored.
OLE DBNative Connectors (Native Accesses) The lock options will have no effect if the locks are not supported by the OLE DB provider or by the Native Connector.
OLE DB The lock mode specified with <Source>.ReadNext will remain effective when <Source>.ReadFirst and <Source>.ReadPrevious are called.
To change the lock mode, use:
Hyper File 5.5 The lock options are ignored. Use the lock functions (<Source>.LockRecNum) kept for backward compatibility.
Remarks

Read operation based on a key

<Source>.Next positions on the next record with the greatest key value. The sort order taken into account is the one specified in the analysis for this key.

Comparison between <Source>.Next and <Source>.ReadNext

<Source>.Next does not read the record: therefore, <Source>.Next is faster than <Source>.ReadNext.

Miscellaneous

WINDEVWEBDEV - Server codeReports and QueriesUniversal Windows 10 AppiPhone/iPadJavaUser code (UMC)External languageAjaxHFSQL ClassicHFSQL Client/ServerHyper File 5.5OLE DBNative Connectors (Native Accesses)

Locks

By default (<Options> not specified), the record is not locked.
If a lock is requested (hLockWrite or hLockReadWrite constant), the position will be set on the record only if it is not already locked.
Component: wd280hf.dll
Minimum version required
  • Version 25
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Last update: 06/21/2023

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