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fbsql_read_blob

(PHP 4 >= 4.2.0, PHP 5, PHP 7)

fbsql_read_blobRead a BLOB from the database

说明

string fbsql_read_blob ( string $blob_handle [, resource $link_identifier ] )

Reads BLOB data from the database.

If a select statement contains BLOB and/or CLOB columns FrontBase will return the data directly when data is fetched. This default behavior can be changed with fbsql_set_lob_mode() so the fetch functions will return handles to BLOB and CLOB data. If a handle is fetched a user must call fbsql_read_blob() to get the actual BLOB data from the database.

参数

blob_handle

A BLOB handle, returned by fbsql_create_blob() .

link_identifier

fbsql_connect() fbsql_pconnect() 返回的 FrontBase 链接标识符.

如可选并未指定,函数会尝试查找一个到 FrontBase 服务器的开放链接,且如没有找到这样的链接,会尝试通过不带参数调用 fbsql_connect() 来创建一个。

返回值

Returns a string containing the specified BLOB data.

范例

Example #1 fbsql_read_blob() example

<?php
$link 
fbsql_pconnect ( "localhost" "_SYSTEM" "secret" )
    or die(
"Could not connect" );
$sql  "SELECT BLOB_COLUMN FROM BLOB_TABLE;" ;
$rs  fbsql_query ( $sql $link );
$row_data  fbsql_fetch_row ( $rs );
// $row_data[0] will now contain the blob data for the first row
fbsql_free_result ( $rs );

$rs  fbsql_query ( $sql $link );
fbsql_set_lob_mode ( $rs FBSQL_LOB_HANDLE );
$row_data  fbsql_fetch_row ( $rs );
// $row_data[0] will now contain a handle to the BLOB data in the first row
$blob_data  fbsql_read_blob ( $row_data [ 0 ]);
fbsql_free_result ( $rs );

?>

参见

  • fbsql_create_blob() - Create a BLOB
  • fbsql_read_clob() - Read a CLOB from the database
  • fbsql_set_lob_mode() - Set the LOB retrieve mode for a FrontBase result set
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