Auto incrementing fields are quite useful, particularly for allocating values to primary keys. MySQL has AUTO_INCREMENT and PostgreSQL has a SERIAL data type. VoltDB has neither, nor anything remotely close to them. This brief article will show you how to simulate auto-incrementing fields in VoltDB. It assumes some knowledge of VoltDB.

VoltDB implements a subset of ANSI-standard SQL. It supports the basic CRUD operations (INSERT, SELECT, UPDATE, DELETE) but it does not have support for automatically generating unique identifiers. It is possible, however, to simulate these in VoltDB, as per this entry in the FAQ. What we can do is create a table that stores the name of the table and the current value that can be used as the unique value for, say, a given column. The schema for the table is shown below:

CREATE TABLE IDENTIFIER (
   TABLE_NAME VARCHAR(100) NOT NULL,
   CURRENT_VALUE INTEGER DEFAULT 1 NOT NULL,
   PRIMARY KEY (TABLE_NAME)
);