Expo SQLite Database isn't initialising in react native

Question

I am trying to create Database for my react native app using expo's SQLite and followed its documentation for it but I think Database isn't initializing.

Documentation: expo-sqlite

App.js:

console.log("init () above");

init()
  .then(() => {
    console.log("DATABASE INITIALIZED");
  })
  .catch(() => {
    console.log("FAILED DATABSE INITIALIZATION", err);
  });

console.log("init () below");

//Nothing logs in console

Console:

init () above
init () below
places: Array []

I created the promise as init() which returns an error if it fails and when it resolves it logs a success message DATABASE INITIALIZED. But I am not getting any output.

helper/db:

import * as SQLite from "expo-sqlite";

const db = SQLite.openDatabase("places.db");

export const init = () => {
  const promiseDB = new Promise((resolve, reject) => {
    db.transaction((tx) => {
      tx.executeSql(
        "CREATE TABLE PLACES IF NOT EXISTS places (id INTEGER PRIMARY KEY NOT NULL, title TEXT NOT NULL, imageUri TEXT NOT NULL, address TEXT NOT NULL, lat REAL NOT NULL, lng REAL NOT NULL)"
      );
      [],
        () => {
          resolve();
        },
        (_, err) => {
          reject(err);
        };
    });
  });
  return promiseDB;
};

I am not getting any errors and also not the success message in the console. I don't know what's the issue and what I am doing wrong?

SamiElk · Accepted Answer · 2022-01-27 14:22:34Z

You didn't write your function correctly, you forgot a curly bracket and added and empty array of arguments where you shouldn't have.

Also in your query you wrote CREATE TABLE PLACES IF NOT EXISTS places. It believe the proper syntax would be CREATE TABLE IF NOT EXISTS places.

The order of arguments in transaction is callback, errorCallback, successCallback. https://docs.expo.dev/versions/latest/sdk/sqlite/#database

The order of the arguments in executeSql is sqlStatement, arguments, callback, errorCallback. https://docs.expo.dev/versions/latest/sdk/sqlite/#sqltransaction

This should create your table:

return new Promise((resolve, reject) => {
        db.transaction(
            function (tx) {
                tx.executeSql("CREATE TABLE IF NOT EXISTS places (id INTEGER PRIMARY KEY NOT NULL, title TEXT NOT NULL, imageUri TEXT NOT NULL, address TEXT NOT NULL, lat REAL NOT NULL, lng REAL NOT NULL)");
            },
            function (error) {
                reject(error.message);
            },
            function () {
                resolve(true);
                console.log('Created database OK');
            }
      );
});

An exemple for when you need to add arguments:

return new Promise((resolve, reject) => {
    db.transaction(
        function (tx) {
            tx.executeSql(
                'SELECT * FROM TABLE_NAME WHERE name=?;',
                [name],
                function (tx, resultSet) {
                    let data = [];
                    for (let i = 0, c = resultSet.rows.length;i < c;i++) {
                        data.push(resultSet.rows.item(i));
                    }
                    resolve(data);
                },
                function (tx, error) {
                    reject(error.message);
                }
            );
        },
        function (error) {
            reject(error.message);
        }
    );
});

Collectives™ on Stack Overflow

Expo SQLite Database isn't initialising in react native

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related