realm database ios

1. Previous Article Data management was implemented with SQLite3 last time, And CoreData was used in this preparation. Core Data is a powerful framework in the iOS SDK. It allows programmers to store and manage Data in an object-oriented manner. With the Core Data framework, programmers can easily and effectively manage Data through object-oriented interfaces. Compared with SQLite3, using CoreData is more helpful for programmers to manage data, In add

If the iOS app uses coredata and has database updates (new tables, fields, and other operations) in the previous version, overwrite the installationProgramTo migrate the coredata database, perform the following operations: 1. Select Your mydata. xcdatamodeld file and choose editor> Add model version from the menu, for example, mydata2.xcdatamodel.2. Set the cur

PrincipleThe correspondence between IOS and SQLModel class structure = SQL table structureModel instance = one row in the SQL tableProperties of the model instance-a column in the SQL tableCorrespondence of model and table@interface Testmodel:nsobject@property (Assign, nonatomic) Nsinteger age; @property (assign, nonatomic) CGFloat height;@ Property (Assign, nonatomic) long distance; @property (assign, nonatomic) double maxdistance; @property (Assign,

PrincipleThe corresponding relationship between IOS and SQLModel class structure = SQL table structureModel instance = one row in the SQL tableProperties of the model instance-a column in the SQL tableThe corresponding model and table@interface Testmodel:nsobject@property (Assign, nonatomic) Nsinteger age; @property (assign, nonatomic) CGFloat height;@ Property (Assign, nonatomic) long distance; @property (assign, nonatomic) double maxdistance; @prope

name = ' WW ' WHERE age is 7;UPDATE t_student SET name = ' Xxoo ' WHERE age UPDATE t_student SET name = ' nnmm ' WHERE age /* Delete Data */DELETE from T_student;/* Update Data */UPDATE t_student SET name = ' LNJ ';/* Insert Data */INSERT into T_student (age, score, name) VALUES (' + ', ' + ', ' Jonathan ');INSERT into T_student (name, age) VALUES (' Lee ', ' 28 ');INSERT into T_student (score) VALUES (100);/* Insert Data */INSERT into T_student (name, age, score) VALUES (' Lee ', ' 28 ', 100);