参考：https://www.postgresql.org/docs/current/static/app-psql.html
postgres=# select * from tab_lei_1; c1 | c2 ----+---- (0 rows) postgres=# \set abc 'tab_lei_1' postgres=# select * from :abc; c1 | c2 ----+---- (0 rows) postgres=#
参考：https://www.postgresql.org/docs/current/static/app-psql.html
postgres=# select * from tab_lei_1; c1 | c2 ----+---- (0 rows) postgres=# \set abc 'tab_lei_1' postgres=# select * from :abc; c1 | c2 ----+---- (0 rows) postgres=#
