ormlite

问题 There have been a few questions on this topic but none giving firm reasons for why there should or shouldn't be a single or multiple instances of the databaseHelper. When is it a good idea to have multiple instances of DatabaseHelper and when is it not. Is less complexity (if that is actually the case ) a good enough reason to have just a single instance ? 回答1: Your DatabaseHelper should be a singleton for sure. Each helper maintains the single connection to the database. If you have multiple

问题 I know nothing about FTS3, except that http://developer.android.com/guide/topics/search/search-dialog.html says performing a full-text search (using FTS3, rather than a LIKE query) can provide a more robust search across text data and can produce results significantly faster I don't see any mention of FTS3 in the ORMLite documentation, though. Is there a way to do this? 回答1: Sorry but there is no direct support for this in ORMLite. If the underlying database supports this then you can use

问题 I have declared my type to be SERIALIZABLE as specified by ORMLite documentation, but I still get: ORMLite can't store unknown class interface java.io.Serializable for field 'task_titles'. Serializable fields must specify dataType=DataType.SERIALIZABLE My code looks like this: @DatabaseField(dataType=DataType.SERIALIZABLE) private Serializable task_titles; public User() { task_titles = new ArrayList<String>(); } I also tried using since ArrayList is serializable but without luck. private

问题 I am working on a JavaFX application in which I am using Ormlite for SQLite database. When I run this application locally in IntelliJ, it works fine. It also works fine when application compiled jar is run. But it is throwing below error, after installing its .deb file and trying to run it. 2018-08-19 15:31:24,763 [INFO] TableUtils creating table 'token' ./wpos: symbol lookup error: /tmp/sqlite-3.7.2-libsqlitejdbc.so: undefined symbol: pthread_mutexattr_init I will add more information if

问题 I am developing an Android application with a sqlite database in an Ubuntu loaded notebook on Intellij IDEA and using database mapping using ormlite. I installed ormlite-android-4.23.jar , ormlite-core-4-1.31.jar , and ormlite-4.23.jar in libs directory of the project folder. I was not sure which version is used here. The application was running and I tried to use my Macbook to proceed with my app development. I am new to Macbook. It is loaded with Mac OS X version 10.5.8. The app is not

问题 I have a column like this: @DatabaseField(dataType = DataType.TIME_STAMP) Timestamp time; When I create the DAO I get this exception: java.lang.IllegalArgumentException: Field class class java.sql.Timestamp for field FieldType:name=time,class=Vote is not valid for data persister com.j256.ormlite.field.types.TimeStampType@334ecfe8 It's been one day that I'm trying different methods and none is working. Note that I have updated my ormlite jar to 4.41. 回答1: Support for java.sql.Timestamp and

问题 i have a little problem for creating an editable ListView. so i have a City Class with two field : id and name , i have created a ObservableList of cities from a database and assigned it to my ListView, and i have created my cellFactory : @DatabaseTable(tableName = "city") public class City { @DatabaseField(generatedId = true) private int id; @DatabaseField private String name; public City() {} } citiesList.setCellFactory(new Callback<ListView<City>, ListCell<City>>() { @Override public

问题 I want to do something like this in OrmLite SELECT *, COUNT(title) as titleCount from table1 group by title; Is there any way to do this via QueryBuilder without the need for queryRaw? 回答1: The documentation states that the use of COUNT() and the like necessitates the use of selectRaw() . I hoped for a way around this - not having to write my SQL as strings is the main reason I chose to use ORMLite. http://ormlite.com/docs/query-builder selectRaw(String... columns): Add raw columns or

问题 I want to know how can i use MAX MIN command with ORMLITE. For example lets say we have this table Table Name = Example Column 1 = id Column 2 = name In ORMLITE how can i get max id ? I looked here but i didnt't understand exactly.. Can someone show me example about Max min in ORMLITE ? 回答1: QueryBuilder<Account, Integer> qb = accountDao.queryBuilder(); qb.selectRaw("MIN(orderCount)", "MAX(orderCount)"); // the results will contain 2 string values for the min and max results = accountDao

问题 quick question about using ORMLite. I am trying to make sure that my implementation is correct. There's a part of the documentation that talks about closableIterators and how accessing this loads the LazyForeignCollection class and it needs to be closed (or read to the end) for the database connection to be closed: NOTE: Like with the Dao.iterator() method, the iterator returned by a lazy collection must be closed when you are done with it because there is a connection open to the database