PE PERSIS ISTIN ING G DATA WIT ITH REALM MOBIL ILE DATABASE - - PowerPoint PPT Presentation
PE PERSIS ISTIN ING G DATA WIT ITH REALM MOBIL ILE DATABASE Adam Fisher Application Developer Integrated Web & Mobile Solutions Team CareSource Xamarin Certified Mobile Developer May 2015 May 2016 July 2017 July
PE PERSIS ISTIN ING G DATA WIT ITH REALM MOBIL ILE DATABASE
Integrated Web & Mobile Solutions Team CareSource
@calmtuna @adamgfisher /adamfisher
KEY/VALUE STORAGE
NSUserDefaults
SharedPreferences
Xamarin.Essentials DATABASE STORAGE
Realm SQLite
Object Oriented Database Relational Database Cross-Platform Cross-Platform Objects Tables, Indexes, Views Remote Cloud Sync
X
Built-in Encryption
X
Live Objects
X
await AsyncStorage.setItem(’ApplicationData', '{ "data": [ { "id": 1, "name": "Bitcoin", "symbol": "BTC", "website_slug": "bitcoin" }, { "id": 2, "name": "Litecoin", "symbol": "LTC", "website_slug": "litecoin" }, { "id": 3, "name": "Namecoin", "symbol": "NMC", "website_slug": "namecoin" }, { "id": 4, "name": "Terracoin", "symbol": "TRC", "website_slug": "terracoin" }, { "id": 5, "name": "Peercoin", "symbol": "PPC", "website_slug": "peercoin" }, { "id": 6, "name": "Novacoin", "symbol": "NVC", "website_slug": "novacoin" }, { "id": 8, "name": "Feathercoin", "symbol": "FTC", "website_slug": "feathercoin" }, { "id": 9, "name": "Mincoin", "symbol": "MNC", "website_slug": "mincoin" }, { "id": 10, "name": "Freicoin", "symbol": "FRC", "website_slug": "freicoin" }, { "id": 13, "name": "Ixcoin", "symbol": "IXC", "website_slug": "ixcoin" }, { "id": 14, "name": "BitBar", "symbol": "BTB", "website_slug": "bitbar" }, { "id": 16, "name": "WorldCoin", "symbol": "WDC", "website_slug": "worldcoin" }, { "id": 18, "name": "Digitalcoin", "symbol": "DGC", "website_slug": "digitalcoin" }, { "id": 25, "name": "GoldCoin", "symbol": "GLD", "website_slug": "goldcoin" }, { "id": 31, "name": "Argentum", "symbol": "ARG", "website_slug": "argentum" }, { "id": 32, "name": "Fastcoin", "symbol": "FST", "website_slug": "fastcoin" }, { "id": 34, "name": "Bitgem", "symbol": "BTG", "website_slug": "bitgem" }, { "id": 35, "name": "Phoenixcoin", "symbol": "PXC", "website_slug": "phoenixcoin" }, { "id": 37, "name": "Megacoin", "symbol": "MEC", "website_slug": "megacoin" }, { "id": 41, "name": "Infinitecoin", "symbol": "IFC", "website_slug": "infinitecoin" }, { "id": 42, "name": "Primecoin", "symbol": "XPM", "website_slug": "primecoin" }, { "id": 43, "name": "Anoncoin", "symbol": "ANC", "website_slug": "anoncoin" }, { "id": 45, "name": "CasinoCoin", "symbol": "CSC", "website_slug": "casinocoin" }, { "id": 49, "name": "Bullion", "symbol": "CBX", "website_slug": "bullion" }, { "id": 50, "name": "Emerald Crypto", "symbol": "EMD", "website_slug": "emerald" }, { "id": 51, "name": "GlobalCoin", "symbol": "GLC", "website_slug": "globalcoin" }, { "id": 52, "name": "XRP", "symbol": "XRP", "website_slug": "ripple" }, { "id": 53, "name": "Quark", "symbol": "QRK", "website_slug": "quark" }, { "id": 56, "name": "Zetacoin", "symbol": "ZET", "website_slug": "zetacoin" }, { "id": 57, "name": "SecureCoin", "symbol": "SRC", "website_slug": "securecoin" }, { "id": 58, "name": "Sexcoin", "symbol": "SXC", "website_slug": "sexcoin" }, { "id": 61, "name": "TagCoin", "symbol": "TAG", "website_slug": "tagcoin" }, { "id": 63, "name": "I0Coin", "symbol": "I0C", "website_slug": "i0coin" }, { "id": 64, "name": "FlorinCoin", "symbol": "FLO", "website_slug": "florincoin" }, { "id": 66, "name": "Nxt", "symbol": "NXT", "website_slug": "nxt" }, { "id": 67, "name": "Unobtanium", "symbol": "UNO", "website_slug": "unobtanium" } ], "metadata": { "timestamp": 1532545712, "num_cryptocurrencies": 66, "error": null } }');
that acts like a database
interconnected, persisted
enforcement
Offline-First Functionality Make your app work as well offline as it does online. Fast Queries Even complex queries take nanoseconds, and stay up to date with new data. Safe Threading Access the same data concurrently from multiple threads, with no crashes. Cross-Platform Apps Use the same database for all your apps, on any major platform. Encryption Secure your data with transparent encryption and decryption. Reactive Architecture Connect your UI to Realm, and data changes will appear automatically.
Realm Relational Database Realm Database /Connection Schema Table Object Row Object.Property Column
and synced Realms
Object Server instance
Windows, Linux
Types Maps To bool JavaScript Boolean values int, float, double JavaScript number values
Internally int and double are stored as 64 bits while float is stored with 32 bits
string string data ArrayBuffer date Date
https://realm.io/docs/javascript/latest/api/tutorial-query-language.html
https://bit.ly/2nrwC7S
and can be less efficient.
part of your predicate statement so it does less work.
should try to minimize the number of write blocks within your code.
const PersonSchema = { name: 'Person', primaryKey: 'id', properties: { id: 'int', // primary key firstName: 'string', lastName: 'string' } };
const CryptocurrencySchema = { name: 'Cryptocurrency', primaryKey: 'symbol', properties: { name: { type: 'string', indexed: true }, symbol: 'string', price: 'double?', marketCap: {type: 'int', default: 0}, founder: 'Person' } };
const ExchangeSchema = { name: 'Exchange', primaryKey: 'name', properties: { name: 'string', websiteUrl: 'string', coins: 'Cryptocurrency[]', } };
Realm.open({schema: [PersonSchema, ExchangeSchema, CryptocurrencySchema]}) .then(realm => { // Create Realm objects and write to local storage realm.write(() => { const bitcoin = realm.create('Cryptocurrency', { name: 'Bitcoin', symbol: 'BTC', price: 7500 }); bitcoin.price += 100; // Update a property value }); // Query Realm for all coins with a high price const coins = realm.objects('Cryptocurrency').filtered('price > 7500'); // Will return a Results object with our 1 coin coins.length; // => 1 // Add another coin realm.write(() => { const eth = realm.create('Cryptocurrency', { name: 'Ethereum', symbol: 'ETH’, price: 7503.24}); }); // Query results are updated in real-time coins.length // => 2 }) .catch(error => { console.log(error); });
try { realm.write(() => { realm.create('Cryptocurrency', {name: 'Dogecoin', symbol: 'DOGE'}); }); } catch (e) { console.log("Error on creation"); }
realm.write(() => { dogecoin.price = 482.11; }); realm.write(() => { // Create a coin object realm.create('Cryptocurrency', { id: 1, title: 'Primecoin', symbol: 'XPM', price: 541.32 }); // Update coin with new price keyed off the id realm.create('Cryptocurrency', {id: 1, price: 482.11}, true); });
realm.write(() => { // Create a coin object let coin = realm.create(‘Cryptocurrency’, { title: 'Potcoin', symbol: 'POT', price: 77.45 }); // Delete the coin realm.delete(coin); // Delete multiple coins by passing in a `Results`, `List`, // or JavaScript `Array` let allCoins = realm.objects('Cryptocurrency'); realm.delete(allCoins); // Deletes all coins });
For to-one relationships you specify the name property of the object schema you are referencing as the property’s type:
const CryptocurrencySchema = { name: 'Cryptocurrency', primaryKey: 'symbol', properties: { // The following property definitions are equivalent founder: {type: 'Person'}, founder: 'Person' } };
const exchange = realm.objects('Exchange').filtered('name = "Coinbase "')[0]; let coins = createCoinObjects(); // <-- Not yet in Realm // exchange.coins = coins; // <-- Error coins = realm.copyToRealmOrUpdate(coins); exchange.coins = coins; // <-- OK
specific property.
const PersonSchema = { name: 'Person', properties: { exchangesOwned: 'Exchange[]' } } const ExchangeSchema = { name: ‘Exchange', properties: { // No shorthand syntax for linkingObjects properties founder: {type: 'linkingObjects', objectType: 'Person', property: 'exchangesOwned'} } }
Realm.open({ schema: [PersonSchema, ExchangeSchema, CryptocurrencySchema], schemaVersion: 1, migration: (oldRealm, newRealm) => { // only apply this change if upgrading to schemaVersion 1 if (oldRealm.schemaVersion < 1) { const oldObjects = oldRealm.objects('Person'); const newObjects = newRealm.objects('Person'); // loop through all objects and set name property in the new schema for (let i = 0; i < oldObjects.length; i++) { newObjects[i].name =
} }}}).then(realm => { const fullName = realm.objects('Person')[0].name; });
const schemas = [ { schema: schema1, schemaVersion: 1, migration: migrationFunction1 }, { schema: schema2, schemaVersion: 2, migration: migrationFunction2 }, ... ] // the first schema to update to is the current schema version // since the first schema in our array is at let nextSchemaIndex = Realm.schemaVersion(Realm.defaultPath); while (nextSchemaIndex < schemas.length) { const migratedRealm = new Realm(schemas[nextSchemaIndex++]); migratedRealm.close(); } // open the Realm with the latest schema Realm.open(schemas[schemas.length-1]);
transactions are committed
receive change metadata on insertions, deletions and updates
notification
function updateUI() { // ... } // Observe Realm Notifications realm.addListener('change', updateUI); // ..later remove the listener realm.removeListener('change', updateUI); // ..or unregister all listeners realm.removeAllListeners();
var key = new Int8Array(64); // populate with a secure key Realm.open({ schema: [PersonSchema, ExchangeSchema, CryptocurrencySchema], encryptionKey: key }) .then(realm => { // Use the Realm as normal var coins = realm.objects('Cryptocurrency'); });
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