mysql hypot_mysqli_stmt_prepare
用戶評論:
[#1]
logos-php at kith dot orgpp [2012-03-23 17:34:02]
Turns?out?you?can't?directly?use?a?prepared?statement?for?a?query?that?has?a?placeholder?in?an?IN()?clause.
There?are?ways?around?that?(such?as?constructing?a?string?that?consists?of?n?question?marks?separated?by?commas,?then?using?that?set?of?placeholders?in?the?IN()?clause),?but?you?can't?just?say?IN?(?).
This?is?a?MySQL?restriction?rather?than?a?PHP?restriction,?but?it's?not?really?documented?in?the?MySQL?docs?either,?so?I?figured?it?was?worth?mentioning?here.
(Btw,?turns?out?someone?else?had?previously?posted?the?info?that?I?put?in?my?previous?comment,?about?not?using?quotation?marks.?Sorry?for?the?repeat;?not?sure?how?I?missed?the?earlier?comment.)
[#2]
logos-php at kith dot org [2012-03-23 07:06:15]
Note?that?if?you're?using?a?question?mark?as?a?placeholder?for?a?string?value,?you?don't?surround?it?with?quotation?marks?in?the?MySQL?query.
For?example,?do?this:
mysqli_stmt_prepare($stmt,?"SELECT?*?FROM?foo?WHERE?foo.Date?>??");
Do?not?do?this:
mysqli_stmt_prepare($stmt,?"SELECT?*?FROM?foo?WHERE?foo.Date?>?'?'");
If?you?put?quotation?marks?around?a?question?mark?in?the?query,?then?PHP?doesn't?recognize?the?question?mark?as?a?placeholder,?and?then?when?you?try?to?use?mysqli_stmt_bind_param(),?it?gives?an?error?to?the?effect?that?you?have?the?wrong?number?of?parameters.
The?lack?of?quotation?marks?around?a?string?placeholder?is?implicit?in?the?official?example?on?this?page,?but?it's?not?explicitly?stated?in?the?docs,?and?I?had?trouble?figuring?it?out,?so?figured?it?was?worth?posting.
[#3]
ndungi at gmail dot com [2009-04-22 02:25:41]
The?`prepare`?,?`bind_param`,?`bind_result`,?`fetch`?result,?`close`?stmt?cycle?can?be?tedious?at?times.?Here?is?an?object?that?does?all?the?mysqli?mumbo?jumbo?for?you?when?all?you?want?is?a?select?leaving?you?to?the?bare?essential?`preparedSelect`?on?a?prepared?stmt.?The?method?returns?the?result?set?as?a?2D?associative?array?with?the?`select`ed?columns?as?keys.?I?havent?done?sufficient?error-checking?and?it?also?may?have?some?bugs.?Help?debug?and?improve?on?it.
I?used?the?bible.sql?db?from?http://www.biblesql.net/sites/biblesql.net/files/bible.mysql.gz.
Baraka?tele!
============================
public$connection;#establish?db?connectionpublic?function__construct($host="localhost",$user="user",$pass="",$db="bible")
{$this->connection=?newmysqli($host,$user,$pass,$db);
if(mysqli_connect_errno())
{
echo("Database?connect?Error?:?".mysqli_connect_error($mysqli));
}
}#store?mysqli?objectpublic?functionconnect()
{
return$this->connection;
}#run?a?prepared?querypublic?functionrunPreparedQuery($query,$params_r)
{$stmt=$this->connection->prepare($query);$this->bindParameters($stmt,$params_r);
if?($stmt->execute())?{
return$stmt;
}?else?{
echo("Error?in$statement:?".mysqli_error($this->connection));
return0;
}
}#?To?run?a?select?statement?with?bound?parameters?and?bound?results.
#?Returns?an?associative?array?two?dimensional?array?which?u?can?easily
#?manipulate?with?array?functions.public?functionpreparedSelect($query,$bind_params_r)
{$select=$this->runPreparedQuery($query,$bind_params_r);$fields_r=$this->fetchFields($select);
foreach?($fields_ras$field)?{$bind_result_r[]?=?&${$field};
}$this->bindResult($select,$bind_result_r);$result_r=?array();$i=0;
while?($select->fetch())?{
foreach?($fields_ras$field)?{$result_r[$i][$field]?=?$$field;
}$i++;
}$select->close();
return$result_r;
}#takes?in?array?of?bind?parameters?and?binds?them?to?result?of
#executed?prepared?stmtprivate?functionbindParameters(&$obj,?&$bind_params_r)
{call_user_func_array(array($obj,"bind_param"),$bind_params_r);
}
private?functionbindResult(&$obj,?&$bind_result_r)
{call_user_func_array(array($obj,"bind_result"),$bind_result_r);
}#returns?a?list?of?the?selected?field?namesprivate?functionfetchFields($selectStmt)
{$metadata=$selectStmt->result_metadata();$fields_r=?array();
while?($field=$metadata->fetch_field())?{$fields_r[]?=$field->name;
}
return$fields_r;
}
}#end?of?class
#An?example?of?the?DB?class?in?use$DB=?newDB("localhost","root","","bible");$var=5;$query="SELECT?abbr,?name?from?books?where?id?>??";$bound_params_r=?array("i",$var);$result_r=$DB->preparedSelect($query,$bound_params_r);#loop?thru?result?array?and?display?resultforeach?($result_ras$result)?{
echo$result['abbr']?."?:?".$result['name']?."
";
}?>
[#4]
kontakt at arthur minus schiwon dot de [2008-06-16 07:22:12]
If?you?wrap?the?placeholders?with?quotation?marks?you?will?experience?warnings?like?"Number?of?variables?doesn't?match?number?of?parameters?in?prepared?statement"?(at?least?with?INSERT?Statements).
[#5]
mhradek AT gmail.com [2008-05-15 16:06:50]
A?particularly?helpful?adaptation?of?this?function?and?the?call_user_func_array?function:
//?$params?is?sent?as?array($val=>'i',?$val=>'d',?etc...)
function?db_stmt_bind_params($stmt,?$params)
{
$funcArg[]?=?$stmt;
foreach($params?as?$val=>$type)
{
$funcArg['type']?.=?$type;
$funcArg[]?=?$val;
}
return?call_user_func_array('mysqli_stmt_bind_param',?$funcArgs);
}
Thanks?to?'sned'?for?the?code.
[#6]
lukaszNOSPAMPLEASE at epas dot pl [2008-01-15 07:15:04]
i've?got?some?bad?news?for?you?guys?if?you?haven't?found?out?already.
the?trick?with?mysqli_next_result()?only?prevents?having?the?connection?dropped?after?a?stored?procedure?call.
apparently?you?can?bind?parameters?for?a?prepared?stored?procedure?call,?but?you'll?get?messed?up?records?from?mysqli_stmt_fetch()?after?mysqli_stmt_bind_result(),?at?least?when?the?stored?procedure?itself?contains?a?prepared?statement.
a?way?to?avoid?data?corruption?could?be?specifying?the?CLIENT_MULTI_STATEMENTS?flag?in?mysqli_real_connect(),?if?it?wasn't?disabled?entirely?(for?security?reasons,?as?they?say).?another?option?is?to?use?mysqli_multi_query(),?but?then?you?can't?bind?at?all.
[#7]
st dot john dot johnson at gmail dot com [2007-06-04 08:59:28]
In?reference?to?what?lachlan76?said?before,?stored?procedures?CAN?be?executed?through?prepared?statements?as?long?as?you?tell?the?DB?to?move?to?the?next?result?before?executing?again.
Example?(Five?calls?to?a?stored?procedure):
<?phpfor ?($i=0;$i<5;$i++)?{$statement=$mysqli->stmt_init();$statement->prepare("CALL?some_procedure(???)");//?Bind,?execute,?and?bind.$statement->bind_param("i",1);$statement->execute();$statement->bind_result($results);
while($statement->fetch())?{//?Do?what?you?want?with?your?results.}$statement->close();//?Now?move?the?mysqli?connection?to?a?new?result.while($mysqli->next_result())?{?}
}?>
If?you?include?the?last?statement,?this?code?should?execute?without?the?nasty?"Commands?out?of?sync"?error.
[#8]
lachlan76 at gmail dot com [2006-11-28 20:59:17]
Do?not?try?to?use?a?stored?procedure?through?a?prepared?statement.
Example:
$statement=$mysqli->stmt_init();$statement->prepare("CALL?some_procedure()");?>
If?you?attempt?to?do?this,?it?will?fail?by?dropping?the?connection?during?the?next?query.??Use?mysqli_multi_query?instead.
Example:
$mysqli->multi_query("CALL?some_procedure()");
do
{$result=$mysqli->store_result();//?Do?your?processing?work?here$result->free();
}?while($mysqli->next_result());?>
This?means?that?you?cannot?bind?parameters?or?results,?however.
[#9]
andrey at php dot net [2005-10-07 05:35:41]
If?you?select?LOBs?use?the?following?order?of?execution?or?you?risk?mysqli?allocating?more?memory?that?actually?used
1)prepare()
2)execute()
3)store_result()
4)bind_result()
If?you?skip?3)?or?exchange?3)?and?4)?then?mysqli?will?allocate?memory?for?the?maximal?length?of?the?column?which?is?255?for?tinyblob,?64k?for?blob(still?ok),?16MByte?for?MEDIUMBLOB?-?quite?a?lot?and?4G?for?LONGBLOB?(good?if?you?have?so?much?memory).?Queries?which?use?this?order?a?bit?slower?when?there?is?a?LOB?but?this?is?the?price?of?not?having?memory?exhaustion?in?seconds.
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