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cubrid_lob2_seek

(PECL CUBRID >= 8.4.1)

cubrid_lob2_seekMove the cursor of a lob object.

说明

bool cubrid_lob2_seek ( resource $lob_identifier , int $offset [, int $origin = CUBRID_CURSOR_CURRENT ] )

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.
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