From 329954981959ee3fc97e52266c89a436d02ddf5e Mon Sep 17 00:00:00 2001 From: "Andrey V. Lepikhov" Date: Tue, 4 Aug 2020 09:29:37 +0500 Subject: [PATCH 1/2] TAP-Test on bad statistics. Add dummy postgres_fdw_stat() routine. It will return stat tuples for each input attribute. --- contrib/postgres_fdw/Makefile | 4 ++-- contrib/postgres_fdw/expected/foreign_stat.out | 18 ++++++++++++++++++ .../postgres_fdw/postgres_fdw--1.0--1.1.sql | 11 +++++++++++ contrib/postgres_fdw/postgres_fdw.c | 17 +++++++++++++++++ contrib/postgres_fdw/postgres_fdw.control | 2 +- contrib/postgres_fdw/sql/foreign_stat.sql | 10 ++++++++++ 6 files changed, 59 insertions(+), 3 deletions(-) create mode 100644 contrib/postgres_fdw/expected/foreign_stat.out create mode 100644 contrib/postgres_fdw/postgres_fdw--1.0--1.1.sql create mode 100644 contrib/postgres_fdw/sql/foreign_stat.sql diff --git a/contrib/postgres_fdw/Makefile b/contrib/postgres_fdw/Makefile index ee8a80a392..15a6f6c353 100644 --- a/contrib/postgres_fdw/Makefile +++ b/contrib/postgres_fdw/Makefile @@ -14,9 +14,9 @@ PG_CPPFLAGS = -I$(libpq_srcdir) SHLIB_LINK_INTERNAL = $(libpq) EXTENSION = postgres_fdw -DATA = postgres_fdw--1.0.sql +DATA = postgres_fdw--1.0.sql postgres_fdw--1.0--1.1.sql -REGRESS = postgres_fdw +REGRESS = postgres_fdw foreign_stat ifdef USE_PGXS PG_CONFIG = pg_config diff --git a/contrib/postgres_fdw/expected/foreign_stat.out b/contrib/postgres_fdw/expected/foreign_stat.out new file mode 100644 index 0000000000..28a470bccc --- /dev/null +++ b/contrib/postgres_fdw/expected/foreign_stat.out @@ -0,0 +1,18 @@ +CREATE TABLE ltable (a int, b real); +CREATE FOREIGN TABLE ftable (a int) server loopback options (table_name 'ltable'); +INSERT INTO ltable (a, b) (SELECT *, 1.01 FROM generate_series(1, 1E4)); +VACUUM; +-- Check statistic interface routine +SELECT * FROM postgres_fdw_stat('public', 'test', 'a'); + postgres_fdw_stat +------------------- + +(1 row) + +EXPLAIN (TIMING OFF, SUMMARY OFF, COSTS ON, ANALYZE) +SELECT * FROM ftable; + QUERY PLAN +--------------------------------------------------------------------------------------------- + Foreign Scan on ftable (cost=100.00..445.00 rows=10000 width=4) (actual rows=10000 loops=1) +(1 row) + diff --git a/contrib/postgres_fdw/postgres_fdw--1.0--1.1.sql b/contrib/postgres_fdw/postgres_fdw--1.0--1.1.sql new file mode 100644 index 0000000000..40d36c95df --- /dev/null +++ b/contrib/postgres_fdw/postgres_fdw--1.0--1.1.sql @@ -0,0 +1,11 @@ +/* contrib/postgres_fdw/postgres_fdw--1.0--1.1.sql */ + +-- complain if script is sourced in psql, rather than via CREATE EXTENSION +\echo Use "CREATE EXTENSION postgres_fdw" to load this file. \quit + +-- Returns serialized stat tuples for the relation attributes +CREATE FUNCTION postgres_fdw_stat(TEXT, TEXT, VARIADIC text[]) +RETURNS json +AS 'MODULE_PATHNAME' +LANGUAGE C STRICT; + diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 9fc53cad68..e4c7bcec49 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -305,6 +305,7 @@ typedef struct * SQL functions */ PG_FUNCTION_INFO_V1(postgres_fdw_handler); +PG_FUNCTION_INFO_V1(postgres_fdw_stat); /* * FDW callback routines @@ -561,6 +562,22 @@ postgres_fdw_handler(PG_FUNCTION_ARGS) PG_RETURN_POINTER(routine); } +/* + * Get stat tuples for the attributes of relation + * See row_to_json() + */ +Datum +postgres_fdw_stat(PG_FUNCTION_ARGS) +{ + const char *nspname = text_to_cstring(PG_GETARG_TEXT_PP(0)); + const char *relname = text_to_cstring(PG_GETARG_TEXT_PP(1)); + StringInfo result; + + result = makeStringInfo(); + + PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len)); +} + /* * postgresGetForeignRelSize * Estimate # of rows and width of the result of the scan diff --git a/contrib/postgres_fdw/postgres_fdw.control b/contrib/postgres_fdw/postgres_fdw.control index f9ed490752..d489382064 100644 --- a/contrib/postgres_fdw/postgres_fdw.control +++ b/contrib/postgres_fdw/postgres_fdw.control @@ -1,5 +1,5 @@ # postgres_fdw extension comment = 'foreign-data wrapper for remote PostgreSQL servers' -default_version = '1.0' +default_version = '1.1' module_pathname = '$libdir/postgres_fdw' relocatable = true diff --git a/contrib/postgres_fdw/sql/foreign_stat.sql b/contrib/postgres_fdw/sql/foreign_stat.sql new file mode 100644 index 0000000000..18f649b477 --- /dev/null +++ b/contrib/postgres_fdw/sql/foreign_stat.sql @@ -0,0 +1,10 @@ +CREATE TABLE ltable (a int, b real); +CREATE FOREIGN TABLE ftable (a int) server loopback options (table_name 'ltable'); +INSERT INTO ltable (a, b) (SELECT *, 1.01 FROM generate_series(1, 1E4)); +VACUUM; + +-- Check statistic interface routine +SELECT * FROM postgres_fdw_stat('public', 'test', 'a'); + +EXPLAIN (TIMING OFF, SUMMARY OFF, COSTS ON, ANALYZE) +SELECT * FROM ftable; -- 2.17.1