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Ce document utilise Manuel du site Web PHP chinois Libérer
(PHP 5 < 5.4.0, PECL sqlite >= 1.0.0)
sqlite_query -- SQLiteDatabase::query — Executes a query against a given database and returns a result handle
$dbhandle
, string $query
[, int $result_type
= SQLITE_BOTH
[, string &$error_msg
]] )$query
, resource $dbhandle
[, int $result_type
= SQLITE_BOTH
[, string &$error_msg
]] )面向对象风格 (method):
$query
[, int $result_type
= SQLITE_BOTH
[, string &$error_msg
]] )
Executes an SQL statement given by the query
against
a given database handle.
dbhandle
The SQLite Database resource; returned from sqlite_open() when used procedurally. This parameter is not required when using the object-oriented method.
query
The query to be executed.
Data inside the query should be properly escaped.
result_type
可选的 result_type
参数接受常量,且决定返回的数组如何被索引。使用
SQLITE_ASSOC
会仅返回关联索引(已命名字段),而
SQLITE_NUM
会仅返回数值索引。 SQLITE_BOTH
会同时返回关联和数值索引。 SQLITE_BOTH
是此函数的默认值。
error_msg
The specified variable will be filled if an error occurs. This is specially important because SQL syntax errors can't be fetched using the sqlite_last_error() function.
Note: 为兼容其他数据库扩展(比如 MySQL),支持两种可替代的语法。推荐第一种格式,函数的第一个参数是
dbhandle
。
This function will return a result handle 或者在失败时返回 FALSE
.
For queries that return rows, the result handle can then be used with
functions such as sqlite_fetch_array() and
sqlite_seek() .
Regardless of the query type, this function will return FALSE
if the
query failed.
sqlite_query() returns a buffered, seekable result handle. This is useful for reasonably small queries where you need to be able to randomly access the rows. Buffered result handles will allocate memory to hold the entire result and will not return until it has been fetched. If you only need sequential access to the data, it is recommended that you use the much higher performance sqlite_unbuffered_query() instead.
版本 | 说明 |
---|---|
5.1.0 |
Added the error_msg parameter
|
SQLite will execute multiple queries separated by semicolons, so you can use it to execute a batch of SQL that you have loaded from a file or have embedded in a script. However, this works only when the result of the function is not used - if it is used, only the first SQL statement would be executed. Function sqlite_exec() will always execute multiple SQL statements.
When executing multiple queries, the return value of this function
will be FALSE
if there was an error, but undefined otherwise (it might
be TRUE
for success or it might return a result handle).
[#1] glenn at byte-consult dot be [2012-01-13 05:16:55]
Not a lot of examples on using the oo style of using sqlite files. Maybe this helps someone trying to figure out all the names of the tables inside an sqlite file.
<?php
class MySQLiteDatabase extends SQLiteDatabase {
public function getTables() {
$tables=array();
$q = $this->query(sprintf("SELECT name FROM sqlite_master WHERE type='table' ORDER BY name"));
$result = $q->fetchAll();
foreach($result as $tot_table) {
$tables[]=$tot_table['name'];
}
return($tables);
}
}
$database="BLAHBLAH.sqlite";
if (file_exists($database)) {
$db = new MySQLiteDatabase($database, 0666, $err);
if ($err) {
trigger_error($err);
} else {
print_r($db->getTables());
}
}
?>
[#2] bruce at causal dot com [2009-08-04 23:11:44]
In follow up to Csaba Gabor's function (see below) that allows for multi-statement queries to be executed via sqlite_query() this alternative implementation avoids a problem with Csaba's version (which prevents multi-statement constructs like CREATE TRIGGER from being parsed correctly).
<?php
function sqlite_query_multi ($db, $query) {
//
// sqlite_query() rewritten to support concatenated SQL statements.
//
// This method works around the sqlite_query() deficiency by splitting
// queries into two parts; the first part comprising all the statements
// except the last one (executed via sqlite_exec) and then the last
// statement (executed via sqlite_query).
//
// This allows the result of the last SELECT statement in a multi-statement
// query to be accessed regardless of the SQL statements that came before it.
// It also allows execution of arbitrary multi-statement programs regardless
// whether the result is needed, subject to the following constraint:
//
// This method requires that the last statement in a multi-statement query
// is a valid "stand-alone" SQL statement. If it is not (eg, the "END;" of
// a multi-statement construct such as CREATE TRIGGER) append an additional
// ";" (ie, a NULL statement). Normally this should not be needed because
// almost all the multi-statement constructs I can think of should have a
// stand-alone statement following them (ie, to makes use of the construct).
//
$pattern = '/^(.*;)(.*;)/s';
if ( preg_match($pattern,$query,$match) ) {
// multi-statement query
sqlite_exec($db,$match[1]);
$result = sqlite_query($db,$match[2]);
} else {
// single-statement query
$result = sqlite_query($db,$query);
}
return (@$result);
}
?>
[#3] helmakil at gmail dot com [2008-02-05 01:58:28]
I suppose this could be useful for users attempting to use a sqlite database for the first time.
<?php
$database = new SQLiteDatabase($yourfile, 0666, $error);
if (!$database) {
$error = (file_exists($yourfile)) ? "Impossible to open, check permissions" : "Impossible to create, check permissions";
die($error);
}
$query = $database->query("SELECT name FROM sqlite_master WHERE type='table'", SQLITE_ASSOC, $query_error); #Lists all tables
if ($query_error)
die("Error: $query_error"); #This means that most probably we catch a syntax error
if (!$query)
die("Impossible to execute query.") #As reported above, this means that the db owner is different from the web server's one, but we did not commit any syntax mistake.
print $query->numRows();
while ($row = $query->fetch())
print($row['name']."\n");
?>
i suppose that the example above is also useful because it will list all the tables created, giving also comprehension of what appens when managing a sqlite database in OO mode.
[#4] jason at fatpipeinc dot com [2005-10-27 07:32:41]
Correction:
sqlite_query will return NULL if the web server cannot write to the sqlite database file.
(please correct the previous post and delete this one)
[#5] jason at fatpipeinc dot com [2005-10-24 09:35:50]
sqlite_open will return NULL if the web server cannot write to the sqlite database file.
I saw the following message in my web server error log:
PHP Warning: sqlite_query(): (null) ...
It turns out that the sqlite database file was owned by a user other than the one the web server was running as. In my case, it was a Linux system running Apache (which was running under the context of user apache). The sqlite database file was owned by root. I changed ownership of the file to user apache and now it works! The sqlite_open call now returns a valid result handle.
Jason Aeschilman
[#6] [2004-10-05 01:54:23]
While reading the manual at sqlite.org, I can answer for the quotes in strings. You should put two quote to get one.
insert into atable values ( '5 O''Clock');
[#7] csaba at alum dot mit dot edu [2004-04-29 18:41:59]
The function below allows you to submit multiple queries in one shot to a SQLITE database, and will return whatever you would get for the final query.
function sqlite_query_multi ($db, $query) {
// submit multiple queries (separated by ;) to $db
// and return the result from the last one
$multiSQL = "/('[^']*'|\"[^\"]*\"|[^;'\"])*;/";
preg_match_all ($multiSQL, "$query;", $aSQL);
for ($i=sizeof($aSQL=$aSQL[0]);$i--;)
if (!($trim=trim(substr($aSQL[$i],0,-1))))
unset ($aSQL[$i]);
else $aSQL[$i] = "$trim;";
foreach ($aSQL as $i => $sql)
$dbRes = sqlite_query ($db, $sql);
return (@$dbRes);
}
The section below illustrates the above function:
$db = sqlite_open(":memory:", 0666, $sqliteerror);
$query = <<<EOD
CREATE TABLE foo (bar INTEGER PRIMARY KEY, baz TEXT);
INSERT INTO foo VALUES (Null, 'Hi');
INSERT INTO foo VALUES (Null, 'Mom');
SELECT * FROM foo;
EOD;
$dbRes = sqlite_query_multi ($db, $query); // 4 statements
while (sqlite_has_more($dbRes))
var_dump(sqlite_fetch_array($dbRes, SQLITE_ASSOC));
Csaba Gabor