How to speed up the process when inserting 1000's of records into sqlite using HTML5

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Iam new to developing HTML5 applications. In this I want to insert 1000\'s of records into sqlite database using HTML5. This process is very slow. How to use BEGIN/COMMIT be

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深忆病人

2021-01-13 10:10

You're starting 1000 transactions. Committing a transaction is slow because it is linked to hard drive speed. See this

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予麋鹿

2021-01-13 10:20

This issue is that you're using a separate transaction for each step, instead of reusing it, hence why it's running poorly.

db.transaction IS a transaction, so no BEGIN/COMMIT needed.

Try this:

<!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>

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攒了一身酷

2021-01-13 10:20
You already have the code to place your 1000 inserts inside a single transaction. For some reason it is commented out. Remove the comments and you are done!
```
db.transaction(function(tx){tx.executeSql("BEGIN",[]);});
for(var i=0;i<1000;i++)
{
    txquer(i,"test");
}
db.transaction(function(tx){tx.executeSql("COMMIT",[]);});
```
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不思量自难忘°

2021-01-13 10:27

I have actually wrote a small open source javascript module called html5sql.js which solves this very problem. The good news is that html5sql.js is really fast. On the website http://html5sql.com I have a demo which creates a table and inserts 11000 records into that table, usually in less than a second or two. If anyone is still dealing with this issue I recommend checking html5sql.js out.

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梦如初夏

2021-01-13 10:30

I solved it , may be this works. Use 'insert select union all' instead of creating 1000 insert statements.But this can insert only 500 rows at a time. Here is the code which i worked on, do a test on google chrome i am sure it works.

<!DOCTYPE HTML>
<html>
<head>
<script type="text/javascript">
var db = openDatabase('mydb', '1.0', 'Test DB', 2 * 1024 * 1024);
var msg;
var j=1;
var i=1;
var quer="";
db.transaction(function(tx){tx.executeSql("CREATE TABLE IF NOT EXISTS LOGS (ID INTEGER PRIMARY KEY ASC, todo TEXT)",[]);});
db.transaction(function(tx){tx.executeSql("delete from logs",[]);});
txquer();
showMsg();
function txquer()
{
  quer="insert into logs ";
 for(i=j;i<=j+498;i++)
 {
  quer+=" select "+i+",'test' union all";
  }
  quer+=" select "+i+",'test' ; ";
  j=i+1;
    db.transaction(
    function(tx){
      tx.executeSql(quer,[]);    
    }
    );

}

function showMsg(){
db.transaction(function (tx) {
  tx.executeSql('SELECT count(*) todo FROM LOGS', [], function (tx, results) {
   var len = results.rows.item(0).todo;
   msg = "<p>Found rows: " + len + "</p>";
   document.querySelector('#status').innerHTML +=  msg;  
 }, null);
});
}

Status Message

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