我是开发HTML5应用程序的新手.在这里我想用HTML5将1000条记录插入sqlite数据库.这个过程非常缓慢.如何在插入记录之前使用BEGIN/COMMIT.以这种方式加快插入.请指导我任何人.提前致谢.请在Chrome浏览器中运行此示例.这是供您参考的代码:
<!DOCTYPE HTML>
<html>
<head>
<script type="text/javascript">
var db = openDatabase('mydb', '1.0', 'Test DB', 2 * 1024 * 1024);
var msg;
//db.transaction(function(tx){tx.executeSql("BEGIN",[]);});
for(var i=0;i<1000;i++)
{
txquer(i,"test");
}
//db.transaction(function(tx){tx.executeSql("COMMIT",[]);});
db.transaction(function (tx) {
tx.executeSql('SELECT * FROM LOGS', [], function (tx, results) {
var len = results.rows.length, i;
msg = "<p>Found rows: " + len + "</p>";
document.querySelector('#status').innerHTML += msg;
}, null);
});
function txquer(i,test)
{
db.transaction(
function(tx){
tx.executeSql('INSERT INTO LOGS (id, log) VALUES (?, ?)',[i,test]);
}
);
}
</script>
</head>
<body>
<div id="status" name="status">Status Message</div>
</body>
</html>
此致,Neeraja.
这个问题是你为每个步骤使用一个单独的事务,而不是重用它,因此它运行得很糟糕.
db.transaction是一个事务,因此不需要BEGIN/COMMIT.
试试这个:
<!DOCTYPE HTML>
<html>
<head>
<script type="text/javascript">
var db = openDatabase('mydb', '1.0', 'Test DB', 2 * 1024 * 1024);
var msg;
db.transaction(function (tx) {
for(var i=0;i<1000;i++)
{
txquer(tx, i,"test");
}
});
db.transaction(function (tx) {
tx.executeSql('SELECT * FROM LOGS', [], function (tx, results) {
var len = results.rows.length, i;
msg = "<p>Found rows: " + len + "</p>";
document.querySelector('#status').innerHTML += msg;
}, null);
});
function txquer(tx,i,test)
{
tx.executeSql('INSERT INTO LOGS (id, log) VALUES (?, ?)',[i,test]);
}
</script>
</head>
<body>
<div id="status" name="status">Status Message</div>
</body>
</html>