Android Room - Select query with LIKE
AndroidKotlinAndroid RoomAndroid Problem Overview
I'm trying to make a query to search all objects whose names contain text:
@Query("SELECT * FROM hamster WHERE name LIKE %:arg0%")
fun loadHamsters(search: String?): Flowable<List<Hamster>>
Messages:
Error:no viable alternative at input 'SELECT * FROM hamster WHERE name LIKE %'
Error:There is a problem with the query: [SQLITE_ERROR] SQL error or missing database (near "%": syntax error)
Error:Unused parameter: arg0
Also I'm trying:
@Query("SELECT * FROM hamster WHERE name LIKE '%:arg0%'")
fun loadHamsters(search: String?): Flowable<List<Hamster>>
Messages:
Error:Unused parameter: arg0
How to fix this?
Android Solutions
Solution 1 - Android
You can just concat using SQLite string concatenation.
@Query("SELECT * FROM hamster WHERE name LIKE '%' || :search || '%'")
fun loadHamsters(search: String?): Flowable<List<Hamster>>
Solution 2 - Android
You should enclose the %
characters in your input query - not in the query itself.
E.g. try this:
@Query("SELECT * FROM hamster WHERE name LIKE :arg0")
fun loadHamsters(search: String?): Flowable<List<Hamster>>
Then your String search
value should look like:
search = "%fido%";
loadHamsters(search);
Furthermore, the binding parameter name should match the variable name, so rather than arg0
it should look like:
@Query("SELECT * FROM hamster WHERE name LIKE :search")
fun loadHamsters(search: String?): Flowable<List<Hamster>>
Solution 3 - Android
Some Example of LIKE Keyword using in dao with Room Database.
-
Start with Search_Query
@Query("SELECT * FROM hamster WHERE name LIKE :search_query || '%'") fun loadHamsters(search_query: String?): Flowable<List<Hamster>>
-
End with Search_Query
@Query("SELECT * FROM hamster WHERE name LIKE '%' || :search_query ") fun loadHamsters(search_query: String?): Flowable<List<Hamster>>
-
Get all which have Search_Query
@Query("SELECT * FROM hamster WHERE name LIKE '%' || :search_query || '%'") fun loadHamsters(search_query: String?): Flowable<List<Hamster>>
-
Use NOT LIKE For except data which have Search_Query
@Query("SELECT * FROM hamster WHERE name NOT LIKE '%' || :search_query || '%'") fun loadHamsters(search_query: String?): Flowable<List<Hamster>>
Solution 4 - Android
Room only supports named bind parameter :name to avoid any confusion between the method parameters and the query bind parameters.
Room will automatically bind the parameters of the method into the bind arguments. This is done by matching the name of the parameters to the name of the bind arguments.
@Query("SELECT * FROM user WHERE user_name LIKE :name AND last_name LIKE :last")
public abstract List<User> findUsersByNameAndLastName(String name, String last);