foreign-keys

I've got the following tables, of which translation is empty and I'm trying to fill: translation { id translated language_id template_id } language { id langname langcode } template { id tplname source domain total } The source data to fill translation is a temporary table that I've populated from an external CSV file: tmp_table { id translated langname tplname source domain } What I'd like to do is to fill translation with the values from tmp_table . The translated field can be copied directly, but I'm not quite sure how to fetch the right language_id (tmp_table.langname could be used to

I am attempting to create a simple database application which keeps track of loans of various types of equipment using Fluent NHibernate and SQLite. However, when I try to generate the database structure with SchemaExport for use in unit testing, foreign keys for one-to-many relationships aren't created. Here is my Equipment entity: public virtual int Id { get; set; } public virtual EquipmentType Type { get; set; } public virtual int StockId { get; set; } And here are my mappings for Equipment : Id(x => x.Id); References(x => x.Type); Map(x => x.StockId); The SQL is generated correctly, except

I created table with FOREIGN KEY and can't insert anything. CREATE TABLE menus ( id int(10), parent_id int(10), label varchar(255), PRIMARY KEY (id), FOREIGN KEY (parent_id) REFERENCES menus (id) ); I need FOREIGN KEY to automatically delete children when parent was deleted. This table was successfully created but I can't insert anything. INSERT INTO `menus` (`parent_id`, `label`) VALUES ('1', 'label1'); or INSERT INTO `menus` (`label`) VALUES ( 'label1'); #1452 - Cannot add or update a child row: a foreign key constraint fails I really don't want look for any children in php code so I need

Our Java application has about 100 classes mapped to a database (SQL Server or MySQL). We are using Hibernate as our ORM (with XML mapping files). We specify FOREIGN KEY constraints in our database schema. Most of our FOREIGN KEY constraints also specify ON DELETE CASCADE . We've recently started enabling Hibernate 2nd level caching (for popular entities and collections) to mitigate some performance problems. Performance has improved since we enabled the 2nd level cache. However we've also started encountering ObjectNotFoundExceptions. It seems the ObjectNotFoundExceptions are occuring because

We use event sourcing with SQL Server 2016. We have total Customer Product Application, each is labelled by CustomerId and gets a single Guide line item in the event store. This is the primary identifier for write event store guids. The Product Applications comes with many different relational things, (which do not have guids but natural keys) each customer has Multiple Addresses, Accounts, Multiple purchase orders. The write event store will be mapped to a relational database tables any way we choose. In databases, we try to relate join by surrogate keys, instead of natural keys. Can the