database-migration

Room 1.1.0 version. I am getting this error on the first run after migration. It runs well if I close the app and start it again. ROOM: Cannot run invalidation tracker. Is the db closed? java.lang.IllegalStateException: Cannot perform this operation because the connection pool has been closed. at android.database.sqlite.SQLiteConnectionPool.throwIfClosedLocked(SQLiteConnectionPool.java:1182) at android.database.sqlite.SQLiteConnectionPool.waitForConnection(SQLiteConnectionPool.java:792) at android.database.sqlite.SQLiteConnectionPool.acquireConnection(SQLiteConnectionPool.java:518) Caused By :

I have a file db_table.py that looks like: from flask import Flask from flask_sqlalchemy import SQLAlchemy from flask_migrate import Migrate app = Flask(__name__) app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:password@localhost/mydb' db = SQLAlchemy(app) migrate = Migrate(app, db) .....db tables.... When I try to run: flask db init I get: Error: Could not locate Flask application. You did not provide the FLASK_APP environment variable. I tried first manually setting FLASK_APP var, by doing set FLASK_APP=app.py then running flask db init again, but that didn't resolve the issue. The

I've got a mission-critical Access 2003 database that changed from a local MDB, to an MDB frontend with the backend on MS SQL Server 2005, using the Microsoft SQL Server Database Migration Assistant (SSMA) software. Now, I need to permanently change the server that the tables are linked to from an IP address (which is changing soon) to a hostname pointing to the same server. The server itself is not changing, just the connection string. It's a DSN-less connection, so the ODBC info is contained within the Access MDB file. If I try to refresh the table links within Access, it prompts me for a

I created a table and added an index to it. On a second migration I renamed the table. Will the index keep on working? Rails 3 No, you'll need to take care of the indexes yourself since the index is based on the table name. For example: remove_index :old_table_name, :column_name rename_table :old_table_name, :new_table_name add_index :new_table_name, :column_name Rails 4+ From the Rails 4 upgrade guide : In Rails 4.0 when a column or a table is renamed the related indexes are also renamed. If you have migrations which rename the indexes, they are no longer needed. 来源： https://stackoverflow.com