I can find syntax "charts" on this on the SQLite website, but no examples and my code is crashing. I have other tables with unique constraints on a single column, but I want to add a constraint to ...

I'm using SQLAlchemy to programmatically query a table with a composite foreign key. e.g.: CREATE TABLE example ( id INT NOT NULL, date TIMESTAMP NOT NULL, data VARCHAR(128) PRIMARY KEY (id, date)...

I have read through handfuls of what would seem to make this a duplicate question. But reading through all of these has left me uncertain. I'm hoping to get an answer based on the absolute example ...

I'm trying to use Spring Data JDBC to access a table that has a compound key, and although I can find lots of info on how Spring Data JPA handles this, the same doesn't seem to apply to Spring Data...

How can you create models (and thus tables) with a compound (composite) primary/unique key using Django?

Say I have the following dataframes: DF1 <- data.frame("A" = rep(c("A","B"), 18), "B" = rep(c("C","D","E"), 12), "NUM"= rep(rnorm(36,10,1)), "TEST" = rep(NA,36)) DF2 <- data.frame("A" = ...

I want to start using dplyr in place of ddply but I can't get a handle on how it works (I've read the documentation). For example, why when I try to mutate() something does the "group_by" functio...

I am trying to better understand utilizing keyd data.tables. After reading the documentation I think I understand how to speed up subsetting when using one key. For example: DT = data.table(x=rep(...

Assuming a table foo with compound primary key (a,b), How I can generate following sql query with SQLAlchemy (postgresql dialect)? SELECT * FROM foo WHERE (a,b) IN ((1,2), (2,3));

I need to store some data in a MySQL-database using Jpa 2/Hibernate 3.5.1. For legacy reasons the table I want to store data in has a compound primary key. The first part of the primary key is of t...

I have a db that's structured with a supertype table as well as subtype tables like so: EVENT PatientId INTEGER, DateTime TEXT, EventTypeCode TEXT, PRIMARY KEY( PatientId, DateTime, EventTypeCode ...

In a legacy database, I have three tables: Users, Workgroups, and UsersWorkgroup. UsersWorkgroup stores what role a user has in a workgroup. Here are the relevant code snippets: @Entity @Table(nam...

I've read that compound primary keys will confuse the hell out of typical ORM code generators. Which ORMs work best with compound PKs and which to avoid? (I've a particular interest in .NET)

I want to make an entity that has an autogenerated primary key, but also a unique compound key made up of two other fields. How do I do this in JPA? I want to do this because the primary key should...