Ionic2 - SQLite executing SQL

Question

I'm creating app with using SQLite. I have some problems with using SQLite.

I have page with variable for managing database.

public sqlite_object: any;

In the constructor i'm opening/creating if not exists database, and saving db object to variable.

constructor(...){
   let name = 'db_name';
   this.openDatabase(name);
}

openDatabase(name){
   let db = new SQLite();
   db.create({ name: name, location: 'default' })
   .then( (db_obj: SQLiteObject) => {
      this.sqlite_object = db_obj
   }, (error) => {
      alert('error');
   }
}

So, in the constructor i'm opening db, and saving it for future. On of buttons calling that function:

testSQL(sql_queries){
   this.sqlite_object.transaction( function(tx){
      Object.keys(sql_queries)
      .sort()
      .forEach( function(v,i){
         tx.executeSql(sql_queries[v],
         null,
         function (transaction, result){
            alert('executing sql');
         },
         function (transaction, error){
            alert('error');
         });
      });
   }, function (error){
      alert('error2');
   }, function (){
      alert('success');
   }
}

My sql_queries have about ~30 queries (correct and incorrect). When i put alert into forEach(), it will be executed everytime (same times as sql_queries length). When executeSql(...) getting incorrect query, alert about error is showing, but i never seen alert 'executing sql' - is sth wrong here? (i don't know if my queries executing correctly)

Also i have one more question. How can i get list of tables from my database?

Sujay · Accepted Answer · 2017-07-31 08:32:17Z

1

your "executing sql.." is inside a success callback function. it will be executed after the entire for each() query is successful (not after each loop). So as you said it's showing error. So, It will not execute the successcallback function. else it will execute the errorcallback function. this is beacause your entire query is not successful. I hope you get the point

answered Jul 31, 2017 at 8:32

Sujay

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1 Comment

Rafał Gołubowicz Over a year ago

ohh, ok , i understand. Maybe you know how can i get list of tables from my db?

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