Implement IMPORT FOREIGN SCHEMA.

This command provides an automated way to create foreign table definitions
that match remote tables, thereby reducing tedium and chances for error.
In this patch, we provide the necessary core-server infrastructure and
implement the feature fully in the postgres_fdw foreign-data wrapper.
Other wrappers will throw a "feature not supported" error until/unless
they are updated.

Ronan Dunklau and Michael Paquier, additional work by me

2 files changed, 17 insertions, 0 deletions

diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index ff203b201fd..e4dedb0c3ba 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -1193,6 +1193,16 @@ DROP TRIGGER trigtest_before_row ON foreign_schema.foreign_table_1;
 DROP TRIGGER trigtest_after_stmt ON foreign_schema.foreign_table_1;
 DROP TRIGGER trigtest_after_row ON foreign_schema.foreign_table_1;
 DROP FUNCTION dummy_trigger();
+-- IMPORT FOREIGN SCHEMA
+IMPORT FOREIGN SCHEMA s1 FROM SERVER s9 INTO public; -- ERROR
+ERROR:  foreign-data wrapper "foo" has no handler
+IMPORT FOREIGN SCHEMA s1 LIMIT TO (t1) FROM SERVER s9 INTO public; --ERROR
+ERROR:  foreign-data wrapper "foo" has no handler
+IMPORT FOREIGN SCHEMA s1 EXCEPT (t1) FROM SERVER s9 INTO public; -- ERROR
+ERROR:  foreign-data wrapper "foo" has no handler
+IMPORT FOREIGN SCHEMA s1 EXCEPT (t1, t2) FROM SERVER s9 INTO public
+OPTIONS (option1 'value1', option2 'value2'); -- ERROR
+ERROR:  foreign-data wrapper "foo" has no handler
 -- DROP FOREIGN TABLE
 DROP FOREIGN TABLE no_table;                                    -- ERROR
 ERROR:  foreign table "no_table" does not exist
diff --git a/src/test/regress/sql/foreign_data.sql b/src/test/regress/sql/foreign_data.sql
index 0f0869ee268..de9dbc8f386 100644
--- a/src/test/regress/sql/foreign_data.sql
+++ b/src/test/regress/sql/foreign_data.sql
@@ -514,6 +514,13 @@ DROP TRIGGER trigtest_after_row ON foreign_schema.foreign_table_1;
 
 DROP FUNCTION dummy_trigger();
 
+-- IMPORT FOREIGN SCHEMA
+IMPORT FOREIGN SCHEMA s1 FROM SERVER s9 INTO public; -- ERROR
+IMPORT FOREIGN SCHEMA s1 LIMIT TO (t1) FROM SERVER s9 INTO public; --ERROR
+IMPORT FOREIGN SCHEMA s1 EXCEPT (t1) FROM SERVER s9 INTO public; -- ERROR
+IMPORT FOREIGN SCHEMA s1 EXCEPT (t1, t2) FROM SERVER s9 INTO public
+OPTIONS (option1 'value1', option2 'value2'); -- ERROR
+
 -- DROP FOREIGN TABLE
 DROP FOREIGN TABLE no_table;                                    -- ERROR
 DROP FOREIGN TABLE IF EXISTS no_table;