database-migration

问题 I have a rather large Core Data-based database schema (~20 entities, over 140 properties) that is undergoing large changes as it migrates from our 1.x code base over to our 2.x code base. I'm very familiar with performing lightweight migrations, but I'm a bit flummoxed with this particular migration because there's a few entities that used to store related objects as transformable attributes on the entity itself, but now I want to migrate those to actual entities. This seems like a perfect

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 3 years ago . So i have an application which currently stores data on an apache server and mysql. I want to migrate to firebase but i have the following problem: My data is a Business table where each user has stored their data. This includes their email and all the data of their business

问题 I have two sql file /migrations v1.0.0__geo-areas-tables.sql v1.0.0__geo-areas-data.sql These files are the same version of the migration. How can I apply them within the limits of migration 1.0.0? P.s. I do not want to use additional scripts combine these files into one. 回答1: The rule is simple: one version = one script. In your case you probably want to name them v1.0.0.0__geo-areas-tables.sql and v1.0.0.1__geo-areas-data.sql as that is the order you want to guarantee anyway. 来源： https:/

问题 I've decided to change my core data structure by adding few relationship (2-3) relationship. How to switch to the new core data stack but still keeping the old implementation (method, data....). Do we need to create new xcdatamodel and how switch to new xcdatamodel? Any help is much appreciate 回答1: When you change your data model, you need to inform CodeData of the change as well. For this a'lightWeightMigration' is needed. To tell Core Data we want to perform a lightweight migration, we need

问题 I recently made a few changes to my Core Data model file and I'm trying to perform a lightweight migration. I've already worked with lightweight migrations before so I know I did all the setup correctly. My only problem is that I changed the type of a relationship: it used to be To-One and now it's To-Many. According to Apple's documentation, lightweight migrations should work just fine in this case, but when I run the code and the system starts migrating the data, there is a crash. I noticed

问题 I am migrating Informix (11.7) DB to PostgreSQL(9.2). There is only one problem: how to move blob(image) from Informix to PostgreSQL(9.2)? Many thanks in advance. 回答1: I did some such conversions between various databases using Jython and JDBC. All you need is Informix and PostgreSQL JDBC drivers in CLASSPATH . I have Informix table with BYTE column, and PostgreSQL table with BYTEA column: -- Informix CREATE TABLE _blob_test ( id integer PRIMARY KEY, image BYTE ) -- PostgreSQL CREATE TABLE

问题 RAISEERROR not supported in SQL Server 2012 RAISERROR 44444 'Field ''CostCodeId'' cannot contain a null value.' How to change the syntax to make it to support in sql server 2012. Any alternative please help. 回答1: In SQL 2012 you should use THROW. Here is link New THROW statement in SQL Server 2012 回答2: For any new development work start using THROW, and if possible start replacing RAISERROR with THROW, as it can be replaced anytime in future (but I don't think in near future). RAISERROR was

问题 We are upgrading our backend for asp.net web application from sql server 2005 to sql server 2008 or 2012. Can you please tell me what will be the impact on the application as a whole. What all changes we would have to do a complete successful transformation. We are also considering in upgrading the front end as well from .Net framework 2.0 to .net framework 4.0 or 4.5. Will it be possible to do both migration together. Please let me know if you need any clarification in the question. 回答1:

问题 This is a long question, but I would be very very thankful if I can get some good advice on this. In short, I’m looking for a good approach for version upgrade of MS SQL database schema that also demands data being moved from deleted tables into new tables. I think Stack Overflow is the most appropriate place for this question (not dba.stackexchange.com) because at its core, this is an issue for .NET developers using Entity Framework, and the database parts of this consists mostly of auto

问题 Please advise on how to migrate my local mysql server to the cloud. Currently I have a Fedora linux box and a NAS attached to it via ethernet. I believe the best way to go about it is : Take a mysqldump of all databases Create an amazon RDS instance and try to load from the created mysqldump Shift local connection to this instance Am I on the right track ? How should I go about doing (1). I have a username and password based access to the mysql server and it has only 1 database. I tried to