Php/docs/function.cubrid-lob2-seek
cubrid_lob2_seek
(PECL CUBRID >= 8.4.1)
cubrid_lob2_seek — Move the cursor of a lob object
说明
cubrid_lob2_seek
( resource $lob_identifier
, int $offset
[, int $origin
= CUBRID_CURSOR_CURRENT
] ) : bool
The cubrid_lob2_seek() function is used to move the cursor
position of a lob object by the value set in the offset
argument, to the direction set in the origin
argument.
To set the origin
argument, you can use CUBRID_CURSOR_FIRST
to set the cursor position moving forward offset
units from
the first beginning. In this case, offset
must be a positive value.
If you use CUBRID_CURSOR_CURRENT for origin
, you can move
forward or backward. and offset
can be positive or negative.
If you use CUBRID_CURSOR_LAST for origin
, you can move
backward offset
units from the end of LOB object and
offset
only can be positive.
参数
lob_identifier
Lob identifier as a result of cubrid_lob2_new() or get from the result set.
offset
Number of units you want to move the cursor.
origin
This parameter can be the following values:
CUBRID_CURSOR_FIRST: move forward from the first beginning.
CUBRID_CURSOR_CURRENT: move forward or backward from the current position.
CUBRID_CURSOR_LAST: move backward at the end of LOB object.
返回值
true
if the process is successful and false
for failure.
范例
Example #1 cubrid_lob2_seek() example
<?php// test_lob (id INT, contents CLOB)$conn = cubrid_connect("localhost", 33000, "demodb", "dba", "");cubrid_execute($conn,"DROP TABLE if exists test_lob");cubrid_execute($conn,"CREATE TABLE test_lob (id INT, contents CLOB)");$req = cubrid_prepare($conn, "INSERT INTO test_lob VALUES(2, ?)");$lob = cubrid_lob2_new($conn, 'CLOB');$len = cubrid_lob2_write($lob, "Hello world");cubrid_lob2_seek($lob, 0, CUBRID_CURSOR_LAST);cubrid_lob2_write($lob, "beautiful");cubrid_lob2_seek($lob, 15, CUBRID_CURSOR_FIRST);$data = cubrid_lob2_read($lob, 5);echo $data."\n";cubrid_lob2_bind($req, 1, $lob);cubrid_execute($req);cubrid_disconnect($conn);?>
参见
- cubrid_lob2_read() - Read from BLOB/CLOB data
- cubrid_lob2_write() - Write to a lob object
- cubrid_lob2_seek64() - Move the cursor of a lob object
- cubrid_lob2_tell() - Tell the cursor position of the LOB object
- cubrid_lob2_tell64() - Tell the cursor position of the LOB object
- cubrid_lob2_size() - Get a lob object's size
- cubrid_lob2_size64() - Get a lob object's size