javascript - SQLError 19 UNIQUE constraint failed - Stack Overflow

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I am getting this error when setting up my app, creating a local database and simply inserting the first and only user (who has logged in locally). Please see ment in code for where I get the error message.

angular.module("greenApp")
.service("dbService",['$q', function($q){

    var db;
    var promise = function(){
        var deferred = $q.defer();

        db = window.openDatabase('greenDB', '1.0', 'Green Database', 2*1024*1024);

        db.transaction(function(tx){
            tx.executeSql("CREATE TABLE IF NOT EXISTS user (user TEXT PRIMARY KEY) ")
        }, function(err){
            alert('Something went wrong... Error: DATABASE INIT ' + err);
        }, function(scc){
            deferred.resolve();
        })

        return deferred.promise;
    }
    promise();

    var query = function(sql, args) {
        var deferred = $q.defer();

        db.transaction(function(tx) {
            tx.executeSql(sql, args, function(tx, results) {
                deferred.resolve(results);
            });
        }, function(err) {
            deferred.reject(err);
        });

        return deferred.promise;
    };

    var insert_into = function(args) {
        var queryPromise = query("INSERT INTO user (user) VALUES (?)", args);
        console.log("in insert_into", queryPromise) // Error message es here
        return queryPromise;
    };

    return {
        promise: promise,
        insert_into: insert_into,
    };
}]);

Where args is simply ["user-name-string"], I get an error message that says:

"could not execute statement due to a constaint failure (19 UNIQUE constraint failed: user.user)

Any ideas what could have happened? Exactly the same code was running and working in a recent pure cordova project which I just ported to Ionic.

I am getting this error when setting up my app, creating a local database and simply inserting the first and only user (who has logged in locally). Please see ment in code for where I get the error message.

angular.module("greenApp")
.service("dbService",['$q', function($q){

    var db;
    var promise = function(){
        var deferred = $q.defer();

        db = window.openDatabase('greenDB', '1.0', 'Green Database', 2*1024*1024);

        db.transaction(function(tx){
            tx.executeSql("CREATE TABLE IF NOT EXISTS user (user TEXT PRIMARY KEY) ")
        }, function(err){
            alert('Something went wrong... Error: DATABASE INIT ' + err);
        }, function(scc){
            deferred.resolve();
        })

        return deferred.promise;
    }
    promise();

    var query = function(sql, args) {
        var deferred = $q.defer();

        db.transaction(function(tx) {
            tx.executeSql(sql, args, function(tx, results) {
                deferred.resolve(results);
            });
        }, function(err) {
            deferred.reject(err);
        });

        return deferred.promise;
    };

    var insert_into = function(args) {
        var queryPromise = query("INSERT INTO user (user) VALUES (?)", args);
        console.log("in insert_into", queryPromise) // Error message es here
        return queryPromise;
    };

    return {
        promise: promise,
        insert_into: insert_into,
    };
}]);

Where args is simply ["user-name-string"], I get an error message that says:

"could not execute statement due to a constaint failure (19 UNIQUE constraint failed: user.user)

Any ideas what could have happened? Exactly the same code was running and working in a recent pure cordova project which I just ported to Ionic.

• javascript
• sql
• angularjs
• cordova
• network-programming

Share Improve this question Follow edited Jul 16, 2015 at 6:28 novalain asked Jul 9, 2015 at 21:10 novalainnovalain 2,2092121 silver badges3939 bronze badges 16

• can u show the table structure also which dbms are u using – Sachu Commented Jul 9, 2015 at 23:54
• r u trying to insert the same text already there in the table? can u show some example? – Sachu Commented Jul 10, 2015 at 9:31
• I'd throw a console.log statement directly inside your insert_into method and double check to make sure args is what you expect it to be and not, for example, null. – Andrew McGivery Commented Jul 10, 2015 at 18:07
• Thanks but I have done that, args is as expected and exactly as stated in the question.. – novalain Commented Jul 13, 2015 at 6:54
• is user the column name? – Vamsi Prabhala Commented Jul 15, 2015 at 12:51

 |  Show 11 more ments

2 Answers 2

Sorted by: Reset to default 3

It looks like you are inserting twice in your code ... here

var insert_into = function(args) {

    var queryPromise = query("INSERT INTO user (user) VALUES (?)", args);
    console.log("in insert_into", queryPromise) // Error message es here
    return query("INSERT INTO user (user) VALUES (?)", args); <-- you did a query above, now you do it again?!?
};

The sqlite db persists when you exit the app, so each time you start the app it will try to do the insert. (I gess it worked at first launch and you got the error the second time).

As you use CREATE TABLE IF NOT EXISTS the app does not fail on table creation but on the first insert.

You can use the pragma user_version to read/write version of your database and so know in wich case you have to create tables / insert values or if the db is already ready to go.

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