Description
resource
sybase_unbuffered_query ( string query, resource link_identifier [, bool store_result] )
Returns a positive Sybase result identifier on success, or
FALSE on error.
Замечание: Эта функция доступна только при
использовании интерфейса к Sybase библиотеки CT, но не библиотеки DB.
sybase_unbuffered_query() sends a query to the
currently active database on the server that's associated with the specified
link identifier. If the link identifier isn't specified, the last
opened link is assumed. If no link is open, the function tries to
establish a link as if sybase_connect() was
called, and use it.
Unlike sybase_query(),
sybase_unbuffered_query() reads only the first
row of the result set. sybase_fetch_array() and similar
function read more rows as needed. sybase_data_seek()
reads up to the target row. The behavior may produce better performance
for large result sets.
sybase_num_rows() will only return the correct number
of rows if all result sets have been read. To Sybase, the number of rows
is not known and is therefore computed by the client implementation.
Замечание:
If you don't read all of the resultsets prior to executing the next query,
PHP will raise a warning and cancel all of the pending results. To get rid of
this, use sybase_free_result() which will cancel pending
results of an unbuffered query.
The optional store_result can be FALSE to indicate
the resultsets shouldn't be fetched into memory, thus minimizing memory usage
which is particularly interesting with very large resultsets.
Пример 1. sybase_unbuffered_query() example
<?php
$dbh = sybase_connect('SYBASE', '', '');
$q = sybase_unbuffered_query('select firstname, lastname from huge_table', $dbh, false);
sybase_data_seek($q, 10000);
$i = 0;
while ($row = sybase_fetch_row($q)) {
echo $row[0], ' ', $row[1], '<br />';
if ($i++ > 40000) {
break;
}
}
sybase_free_result($q);
sybase_close($dbh);
?>
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See also
sybase_query().