Glossary

The vocabulary used throughout the docs.

ARIES
The recovery algorithm Numstore uses. On open, work from committed transactions is redone and work from transactions that never committed is undone. See Durability and crash recovery.

Automatic transaction
The transaction a query gets when you don't hand it one - the query happens completely or not at all, and it's durable by the time the call returns.

C order
How strict arrays are laid out in memory: the last dimension is contiguous. Also called row-major order. See The type system.

dtype
The numpy data type of one element. ns.to_dtype gives the dtype of a Numstore type.

Plan
A compiled query you can run as many times as you like. See Reuse a query with a plan.

Primitive
A type with no members, like u32 or cf64. At the bottom of every type is a primitive.

Smart file
One untyped byte array in a file, with no variables but the same ACID guarantees as a database. See Use smart files.

Strict array
A type with fixed dimensions, for example [256][256] f32.

Struct
A type whose members are stacked back to back, with no padding.

Union
A type whose members are overlayed, all starting at the same byte. Its size is the size of its largest member.

Variable
A name, a type and one array. A database maps variables to arrays.