GreenDao is an ORM library that provides high performance for CRUD operations on SQLite databases in Android apps. It uses code generation to map objects to database tables, allowing data to be accessed and queried using objects rather than raw SQL. Some key features include object mapping, query building, caching, and bulk operations. The documentation provides examples of how to set up GreenDao in a project, define entity classes, perform queries, inserts, updates and deletes on objects.

1. GreenDao
綠道
Heaton

2. Outline
• Why GreenDao
• Feature
• Performance
• How to getting start
• How to use.

3. Why GreenDao
• First . Some problem with DB Development.
– No object orientation.
– Data access sentence is low levely.
– Always make same code to write SQL script.
– Do you know SQL without 『||』.
– I am stupid on SQL tuning
• Second , it is faster than other ORM Lib.

4. It is popular?

5. Features
• High Performance
– CRD test.
• ORM (Object relation mapping)
– Code Generation
– Read and write objects
– CREATE TABLE done for you
– Expressing Queries
• Session cache
• Setter ; getter
• Create table “table_name”
• Return List<Common>

6. Performance
• Test case :
– insert 10000 row
– delete 10000 row
– query 20000 row
Test 1 Dao Content Provider
Insert 1467 87268 (no transcation)
Load 1608 9797
Delete 108 121
Test 2
Insert 662 87766
Load 1837 12282
delete 137 127

7. Benchmark
• https://github.com/daj/android-orm-
benchmark
• Write 10000
• Read 10000

8. ORM
Object/relation mapping (ORM)

9. A example for presentation
• Implement a social data collector
• “Leftpage” as table name for database
“leftpageProvider.db”
• Every row data as “CommonData”
• Column has
– ”DataID” as primary key
– “Category”
– “Provider”
– “DisplayOrder”

10. Expressing Queries: What difference
• SQL Query all
– Cursor c =
mContext.getContentResolver().query(uriLPagePr
ovider , projection , selection, selection args, sort
order ) ;
• GreenDao Load all
List<commonData> datas =
CommonDataDao.loadAll();

11. Sqlite review
• SQL Query
– Provider equal facebook
– Order by display order
– Limit data count100
• Cursor c = getContentResolver() . query
(uriLPageProvider , projection , selection,
selection args, sort order ) ;
(String ) selection :
StorageField.Provider. + "=?" =
(String[])selection args: {“facebook”}

12. Sort order
• SQL Query
– Provider equal facebook
– Order by display order
– Limit data count100
• Cursor c = getContentResolver() . query
(uriLPageProvider , projection , selection,
selection args, sort order ) ;
(String ) Sort order: StorageField.Displayorder

13. More detail
• SQL Query
– Provider equal facebook
– Order by display order
– Limit data count100
• Cursor c = getContentResolver() . query
(uriLPageProvider , projection , selection,
selection args, sort order ) ;
(String ) Sort order:
“ ASC ” + StorageField.Displayorder
+ “ LIMIT ” + request

14. If you are sqlite master
• SQL Query
– Provider equal facebook
– Order by display order
– Limit data count100
• Select * from leftpage where Provider =
‘facebook’ order asc ‘displayorder’ limit
‘100’
• Then you also load cusor and save to data
list

15. But in GreenDao
• SQL Query
– Provider equal facebook
– Order by display order
– Limit data count100
mCommonDataDao.queryBuilder()
.where(Properties.Provider.eq(Provider.Facebook))
.orderAsc(Properties.DisplayOrder)
.limit(100)
.list();

16. HOW TO GETTING START
Create module

17. How to getting start?
First time is terrible

18. Create a module to gen greendao code
• In module gradle
– Add Gradle script
– compile 'de.greenrobot:greendao-generator:1.3.1

19. Create main() in our case.
public class GreenDao {
public static void main(String[] args){
Schema schema = new Schema
(1, "com.acer.android.leftpage.provider");
Entity commonData = schema.addEntity("commonData");
commonData.setTableName("LeftPage");
commonData.addLongProperty("DataID").primaryKey();
commonData.addStringProperty("Category");
commonData.addStringProperty("Provider");
commonData.addLongProperty(“DisplayOrder”);
commonData.addContentProvider();
DaoGenerator generator = new DaoGenerator();
generator.generateAll
(schema, "../AcerHome/LeftPage/src/main/java/");}

20. Compile and run to Auto gen Core
classes
DaoMaster
DaoSeesion
CommonDataDao
CommonData

21. In CommonDataDao
public static void createTable(SQLiteDatabase db, boolean ifNotExists) {
String constraint = ifNotExists? "IF NOT EXISTS ": "";
db.execSQL("CREATE TABLE " + constraint + "'LeftPage' (" + //
"'DataID' INTEGER PRIMARY KEY AUTOINCREMENT ," + // 0:
DataID
"'Category' TEXT," + // 1: Category
"'Provider' TEXT," + // 2: Provider
"'DisplayOrder' INTEGER DEFAULT -1," + // 3: DisplayOrder
"'Bookmarked' INTEGER DEFAULT 0," + // 4: Bookmarked
"'Deleted' INTEGER DEFAULT 0," + // 5: Deleted
"'Score' REAL DEFAULT -1," + // 6: Score
"'Keywords' TEXT DEFAULT NULL," + // 7: Keywords

22. CommonData content
public Long getDataID() { return DataID; }
public void setDataID(Long DataID) {
this.DataID = DataID; }
……
……
……

23. Add it and start to use
• In Used Project gradle
– compile 'de.greenrobot:greendao:1.3.7'

24. HOW TO USE
INSERT , DELETE , UPDATE,

25. Initial
• DaoMaster.DevOpenHelper helper = new
DaoMaster.DevOpenHelper(context,”leftpage
provider.db”);
• DaoMaster master = new DaoMaster
(helper.getDataBase());
• DaoSession session = master.newSession();
• CommonDataDao CommonDataDao=
session.getCommonDataDao();

26. Query
• Query with syntax
– eq , notEq
– ge , le , gt , lt
– in , between
– like
• List<commonData> dataList =
CommonDataDao.queryBuilder()
.where(Properties.Provider.eq(Provider.Social))
.orderAsc(mCommonDataDao.Properties.DisplayOrder)
.list();

27. Raw query
SQLiteDatabase db =
daoSession.getDatabase();
Cursor cursor = db.rawQuery("SELECT *FROM
leftpage WHERE .....", null);

28. Insert
• Insert:
– CommonDataDao .insert(new CommonData(DATA_ID,
arg1, arg2,x……));
• Bulk Insert
– CommonDataDao .insertln(CommonDataList);
– CommonDataDao.insertln(CommonData[]);
• InsetOrReplace
– CommonDataDao.insertOrReplaceln(CommonDataList)
Note: DATA_ID usually is null .

29. Delete
• Delete sentence
– CommonDataDao.QueryBuilder()
.where(Properties.Provider.eq(facebook))
.buildDelete()
.executeDeleteWithoutDetachingEntities();
• Delete all
– CommonDataDao.deleteAll();

30. Update
• Update sentence
– CommonDataDao.update(new
CommonData(Data_ID , arg1 , arg2 , …….));
• Bulk Update
– CommonDataDao.updateln(CommonDataList);
– CommonDataDao.updateln(CommonData[]);
Note: DATA_ID must assign what
the row you want to update.

31. Thanks
Reference:
http://greendao-orm.com/features/
http://bng86.gitbooks.io/android-third-party-
/content/greendao.html
http://www.slideshare.net/SmileeYang/greendao-
43892958?qid=b95e0f35-a323-4930-8e8a-
d0e298a1eb10&v=qf1&b=&from_search=1
http://www.slideshare.net/ssuser8674c1/green-dao-
50914708?qid=b95e0f35-a323-4930-8e8a-
d0e298a1eb10&v=qf1&b=&from_search=5

32. Something here
AsyncSession asyncSession =
DBHelper.getInstance(this).getAsyncSession();
asyncSession.insert(
new CommonData(null, …, …));