The following way works with 2 commands:
zhifan=# create table t1 (a jsonb);
CREATE TABLE
zhifan=# create unique index t1_a_name on t1 ((a->'name'));
CREATE INDEX
but know I want to merge them into 1 command, is it possible?
zhifan=# create table t2 (a jsonb, constraint uk_t2_a_name unique((a->'name')));
ERROR: syntax error at or near "("
LINE 1: ...table t2 (a jsonb, constraint uk_t2_a_name unique((a->'name'...