Column key schema

A column key consists of two case-sensitive components, separated by : (colon):

• column family name
• column qualifier

Columns are grouped under column families. To access a column, use the family’s name and a column qualifier. For instance, to access the column size inside the meta column family, the column key would be meta:size.

Note

Column qualifiers in Bigtable can be arbitrary byte arrays. In Smoltable, they need to be valid UTF-8 strings.

Default column

The column qualifier can be omitted to access the default column (empty). For instance, if we wanted to have a single column family that stores a title, the column would be accessed by title:. In that case, the : can be omitted: title.