Chapter 9. Data Model

Table of Contents

9.1. Table
9.2. Row
9.3. Column Family
9.4. Cells
9.5. Versions
9.5.1. Versions and HBase Operations
9.5.2. Current Limitations

In short, applications store data into HBase tables. Tables are made of rows and columns. All colums in HBase belong to a particular Column Family. Table cells -- the intersection of row and column coordinates -- are versioned. A cell’s content is an uninterpreted array of bytes.

Table row keys are also byte arrays so almost anything can serve as a row key from strings to binary representations of longs or even serialized data structures. Rows in HBase tables are sorted by row key. The sort is byte-ordered. All table accesses are via the table row key -- its primary key.

9.1. Table

Tables are declared up front at schema definition time.