I am at my wits end with a problem I cannot resolve - when trying to change the schema/data of a table in my database. I am pre-populating the database with Rooms .createFromAsset method.
Current schema and data (working) - as shown in DB Browser - this is the database used to Pre-Populate the apps database.
As I build the database with this code:
val instance = Room.databaseBuilder(
context.applicationContext,
MetarDatabase::class.java,
"metar_database"
)
.createFromAsset("database/metar_database.db")
.fallbackToDestructiveMigration()
.build()
And this data class:
@Entity(tableName = "airport_table")
data class Airport(
@PrimaryKey(autoGenerate = false)
val icao : String,
val name : String?,
val municipality : String?,
val scheduled : Boolean,
val iata : String?
)
It successfully pre-populates the database into the app: as seen on Database Explorer:
The problem is this: If I try and change the schema at all: adding columns, removing columns (done by changing a csv file and importing into a new table in DB Browser, then re-naming to airport_table and adding one to the database version), it does not load the data.
Eg: (Does NOT pre-populate):
@Entity(tableName = "airport_table")
data class Airport(
@PrimaryKey(autoGenerate = false)
val icao : String,
val name : String?
)
I get NO errors apart from "E/libc: Access denied finding property "ro.serialno"" which I don't think is relevant.
In addition - changing this one table means that my other table does not pre-populate. However the empty database has still been made successfully, and I can add to it within the app.
Please help me - I've looked around stack overflow for similar questions. Some are similar, but involve getting anything to happen at all - my problem is it only works with one exact schema that I happen to succeed with whilst testing - but I want another schema.
Thanks a lot, Liam
from Cannot pre-populate room database when changing schema
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