dbQuerySeek#
Purpose#
Retrieves the record at a specified position, if available, and positions the query on the retrieved record.
Format#
- ret = dbQuerySeek(qid, idx[, idx_type])#
- Parameters:
qid (scalar) – query number.
idx (scalar) – the index at which to place the cursor.
idx_type (scalar) – 1 for relative position or 0 for absolute positioning. If not specified, absolute positioning is used.
- Returns:
ret (scalar) – 1 if successful.
Remarks#
The first record is at position 1. Note that the query must be in an
active state before calling this function. The state of the query may be
verified with the function dbQueryIsSelect()
.
If idx_type is 0 (the default), the following rules apply:
If idx is negative, the result is positioned before the first record and 0 is returned. Otherwise, an attempt is made to move to the record at position idx. If the record at position idx could not be retrieved, the result is positioned after the last record and 0 is returned. If the record is successfully retrieved, 1 is returned.
If idx_type is 1, the following rules apply:
If the result is currently positioned before the first record or on the first record, and idx is negative, there is no change, and 0 is returned.
If the result is currently located after the last record, and idx is positive, there is no change, and 0 is returned.
If the result is currently located somewhere in the middle, and the relative offset idx moves the result below zero, the result is positioned before the first record and 0 is returned.
Otherwise, an attempt is made to move to the record idx records ahead of the current record (or idx records behind the current record if idx is negative).
If the record at offset idx could not be retrieved, the result is positioned after the last record if \(idx >= 0\), (or before the first record if idx is negative), and 0 is returned. If the record is successfully retrieved, 1 is returned.
See also
Functions dbQuerySeekFirst()
, dbQuerySeekLast()
, dbQuerySeekNext()
, dbQuerySeekPrevious()