注意
此功能需加载插件 pg_trgm。

teledb=# create extension pg_trgm;
CREATE EXTENSION
teledb=# create table t_trgm (id int,trgm text,no_trgm text) ;
ERROR:  relation "t_trgm" already exists
teledb=# create index t_trgm_trgm_idx on t_trgm using gist(trgm gist_trgm_ops);
CREATE INDEX