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DBSEEK()
Move to the record having the specified key value
------------------------------------------------------------------------------
Syntax
DBSEEK(<expKey>, [<lSoftSeek>], [<lLast>]) --> lFound
Arguments
<expKey> is a value of any type that specifies the key value
associated with the desired record.
<lSoftSeek> is an optional logical value that specifies whether a
soft seek is to be performed. This determines how the work area is
positioned if the specified key value is not found (see below). If
<lSoftSeek> is omitted, the current global _SET_SOFTSEEK setting is
used.
<lLast> is specified as true (.T.) to seek the last occurrence of
the specified key value. False (.F.), the default, seeks the first
occurrence.
Note: This parameter is only supported for specific RDDs. DBFNTX
is NOT one of them.
Returns
DBSEEK() returns true (.T.) if the specified key value was found;
otherwise, it returns false (.F.).
Description
DBSEEK() moves to the first logical record whose key value is equal to
<expKey>. If such a record is found, it becomes the current record and
DBSEEK() returns true (.T.); otherwise, it returns false (.F.). the
positioning of the work area is as follows: for a normal (not soft)
seek, the work area is positioned to LASTREC() + 1 and EOF() returns
true (.T.); for a soft seek, the work area is positioned to the first
record whose key value is greater than the specified key value. If no
such record exists, the work area is positioned to LASTREC() + 1 and
EOF() returns true (.T.).
For a work area with no active indexes, DBSEEK() has no effect.
DBSEEK() performs the same function as the standard SEEK command. For
more information, refer to the SEEK command.
Notes
. Logical records: DBSEEK() operates on logical records which
are considered in indexed order. If a filter is set, only records
which meet the filter condition are considered.
. Controlling order: If the work area has more than one active
index, the operation is performed using the controlling order as set
by DBSETORDER() or the SET ORDER command. For more information,
refer to the SET ORDER command.
. Network environment: For a shared file on a network, moving
to a different record may cause updates to the current record to
become visible to other processes. For more information, refer to
the "Network Programming" chapter in the Programming and Utilities
Guide. This function will not affect the locked status of any
record.
Examples
. In this example, DBSEEK() moves the pointer to the record in
the database, Employee, in which the value in FIELD "cName" matches
the entered value of cName:
ACCEPT "Employee name: " TO cName
IF ( Employee->(DBSEEK(cName)) )
Employee->(VIEWRECORD())
ELSE
? "Not found"
END
Files Library is CLIPPER.LIB.
See Also:
DBGOBOTTOM()
DBGOTOP()
DBSKIP()
EOF()
FOUND()
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