cubrid_lob2_seek
(PECL CUBRID >= 8.4.1)
cubrid_lob2_seek — Move the cursor of a lob object
说明
$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
