Two kinds of identity column: GENERATED ALWAYS AS IDENTITY example: create table greatings (i int generated always as identity);
GENERATED BY DEFAULT AS IDENITY. example: create table greatings (i int generated by default as identity); The difference is you cannot specify particular value for the GENERATE ALWAY, but you can do so for the later. What's more, GENERATE BY DEFAULT doesn't guarantee uniqueness. You can use a primary key or unique constraint on the GENERATE BY DEFAULT identity column. --- "Jean T. Anderson" <[EMAIL PROTECTED]> Wrote: > Since others on derby-user might have the same > question.... > > Question on #derby IRC: > > derby newbie here... Does anyone know if there is a > way to create auto > increment columns in derby like mysql? > > Answer given: > > derby supports identity columns : see > http://db.apache.org/derby/docs/10.1/ref/rrefsqlj24513.html > and the full info for generated ... as identity is > at > http://db.apache.org/derby/docs/10.1/ref/rrefsqlj37836.html > ___________________________________________________________ 雅虎1G免费邮箱百分百防垃圾信 http://cn.mail.yahoo.com/
