timescaledb/sql/size_utils.sql
Erik Nordström 097db3d589 Refactor chunk index handling
This change refactors the chunk index handling to make better use
of standard PostgreSQL catalog information, while removing the
hypertable_index metadata table and associated triggers, including
those on the chunk_index table. The chunk_index table itself is
also simplified.

A benefit of this refactoring is that indexes are no longer
created using string mangling to construct the CREATE INDEX command
for a chunk, based on the string definition of the hypertable
index. Instead, indexes are created in C using proper index-related
internal data structures.

Chunk indexes can now also be renamed and are added in the parent
index tablespace. Changing tablespace on a hypertable index also
recurses to chunks, as expected. Default indexes that are added when
creating a hypertable use the hypertable's tablespace.

Creating Hypertable indexes with the CONCURRENTLY modifier is
currently blocked, due to unclear semantics regarding concurrent
creation over many tables, including how to deal with snapshots.
2017-10-03 10:51:32 +02:00

416 lines
15 KiB
PL/PgSQL

-- This file contains utility functions to get the relation size
-- of hypertables, chunks, and indexes on hypertables.
-- Get relation size of hypertable
-- like pg_relation_size(hypertable)
-- (https://www.postgresql.org/docs/9.6/static/functions-admin.html#FUNCTIONS-ADMIN-DBSIZE)
--
-- main_table - hypertable to get size of
--
-- Returns:
-- table_bytes - Disk space used by main_table (like pg_relation_size(main_table))
-- index_bytes - Disc space used by indexes
-- toast_bytes - Disc space of toast tables
-- total_bytes - Total disk space used by the specified table, including all indexes and TOAST data
CREATE OR REPLACE FUNCTION hypertable_relation_size(
main_table REGCLASS
)
RETURNS TABLE (table_bytes BIGINT,
index_bytes BIGINT,
toast_bytes BIGINT,
total_bytes BIGINT
) LANGUAGE PLPGSQL STABLE
AS
$BODY$
DECLARE
table_name NAME;
schema_name NAME;
BEGIN
SELECT relname, nspname
INTO STRICT table_name, schema_name
FROM pg_class c
INNER JOIN pg_namespace n ON (n.OID = c.relnamespace)
WHERE c.OID = main_table;
RETURN QUERY EXECUTE format(
$$
SELECT table_bytes,
index_bytes,
toast_bytes,
total_bytes
FROM (
SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM (
SELECT
sum(pg_total_relation_size('"' || c.schema_name || '"."' || c.table_name || '"'))::bigint as total_bytes,
sum(pg_indexes_size('"' || c.schema_name || '"."' || c.table_name || '"'))::bigint AS index_bytes,
sum(pg_total_relation_size(reltoastrelid))::bigint AS toast_bytes
FROM
_timescaledb_catalog.hypertable h,
_timescaledb_catalog.chunk c,
pg_class pgc,
pg_namespace pns
WHERE h.schema_name = %L
AND h.table_name = %L
AND c.hypertable_id = h.id
AND pgc.relname = h.table_name
AND pns.oid = pgc.relnamespace
AND pns.nspname = h.schema_name
AND relkind = 'r'
) sub1
) sub2;
$$,
schema_name, table_name);
END;
$BODY$;
CREATE OR REPLACE FUNCTION _timescaledb_internal.range_value_to_pretty(
time_value BIGINT,
column_type REGTYPE
)
RETURNS TEXT LANGUAGE PLPGSQL STABLE AS
$BODY$
DECLARE
BEGIN
IF time_value IS NULL THEN
RETURN format('%L', NULL);
END IF;
CASE column_type
WHEN 'BIGINT'::regtype, 'INTEGER'::regtype, 'SMALLINT'::regtype THEN
RETURN format('%L', time_value); -- scale determined by user.
WHEN 'TIMESTAMP'::regtype, 'TIMESTAMPTZ'::regtype THEN
-- assume time_value is in microsec
RETURN format('%1$L', _timescaledb_internal.to_timestamp(time_value)); -- microseconds
WHEN 'DATE'::regtype THEN
RETURN format('%L', timezone('UTC',_timescaledb_internal.to_timestamp(time_value))::date);
ELSE
RETURN time_value;
END CASE;
END
$BODY$;
CREATE OR REPLACE FUNCTION _timescaledb_internal.partitioning_column_to_pretty(
d _timescaledb_catalog.dimension
)
RETURNS TEXT LANGUAGE PLPGSQL STABLE AS
$BODY$
DECLARE
BEGIN
IF d.partitioning_func IS NULL THEN
RETURN d.column_name;
ELSE
RETURN d.partitioning_func_schema || '.' || d.partitioning_func
|| '(' || d.column_name || ')';
END IF;
END
$BODY$;
-- Get relation size of hypertable
-- like pg_relation_size(hypertable)
-- (https://www.postgresql.org/docs/9.6/static/functions-admin.html#FUNCTIONS-ADMIN-DBSIZE)
--
-- main_table - hypertable to get size of
--
-- Returns:
-- table_size - Pretty output of table_bytes
-- index_bytes - Pretty output of index_bytes
-- toast_bytes - Pretty output of toast_bytes
-- total_size - Pretty output of total_bytes
CREATE OR REPLACE FUNCTION hypertable_relation_size_pretty(
main_table REGCLASS
)
RETURNS TABLE (table_size TEXT,
index_size TEXT,
toast_size TEXT,
total_size TEXT) LANGUAGE PLPGSQL STABLE
AS
$BODY$
DECLARE
table_name NAME;
schema_name NAME;
BEGIN
RETURN QUERY
SELECT pg_size_pretty(table_bytes) as table,
pg_size_pretty(index_bytes) as index,
pg_size_pretty(toast_bytes) as toast,
pg_size_pretty(total_bytes) as total
FROM hypertable_relation_size(main_table);
END;
$BODY$;
-- Get relation size of the chunks of an hypertable
-- like pg_relation_size
-- (https://www.postgresql.org/docs/9.6/static/functions-admin.html#FUNCTIONS-ADMIN-DBSIZE)
--
-- main_table - hypertable to get size of
--
-- Returns:
-- chunk_id - Timescaledb id of a chunk
-- chunk_table - Table used for the chunk
-- partitioning_columns - Partitioning column names
-- partitioning_column_types - Type of partitioning columns
-- partitioning_hash_functions - Hash functions of partitioning columns
-- ranges - Partition ranges for each dimension of the chunk
-- table_bytes - Disk space used by main_table
-- index_bytes - Disk space used by indexes
-- toast_bytes - Disc space of toast tables
-- total_bytes - Disk space used in total
CREATE OR REPLACE FUNCTION chunk_relation_size(
main_table REGCLASS
)
RETURNS TABLE (chunk_id INT,
chunk_table TEXT,
partitioning_columns NAME[],
partitioning_column_types REGTYPE[],
partitioning_hash_functions TEXT[],
ranges int8range[],
table_bytes BIGINT,
index_bytes BIGINT,
toast_bytes BIGINT,
total_bytes BIGINT)
LANGUAGE PLPGSQL STABLE
AS
$BODY$
DECLARE
table_name NAME;
schema_name NAME;
BEGIN
SELECT relname, nspname
INTO STRICT table_name, schema_name
FROM pg_class c
INNER JOIN pg_namespace n ON (n.OID = c.relnamespace)
WHERE c.OID = main_table;
RETURN QUERY EXECUTE format(
$$
SELECT chunk_id,
chunk_table,
partitioning_columns,
partitioning_column_types,
partitioning_hash_functions,
ranges,
table_bytes,
index_bytes,
toast_bytes,
total_bytes
FROM (
SELECT *,
total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes
FROM (
SELECT c.id as chunk_id,
'"' || c.schema_name || '"."' || c.table_name || '"' as chunk_table,
pg_total_relation_size('"' || c.schema_name || '"."' || c.table_name || '"') AS total_bytes,
pg_indexes_size('"' || c.schema_name || '"."' || c.table_name || '"') AS index_bytes,
pg_total_relation_size(reltoastrelid) AS toast_bytes,
array_agg(d.column_name ORDER BY d.interval_length, d.column_name ASC) as partitioning_columns,
array_agg(d.column_type ORDER BY d.interval_length, d.column_name ASC) as partitioning_column_types,
array_agg(d.partitioning_func_schema || '.' || d.partitioning_func ORDER BY d.interval_length, d.column_name ASC) as partitioning_hash_functions,
array_agg(int8range(range_start, range_end) ORDER BY d.interval_length, d.column_name ASC) as ranges
FROM
_timescaledb_catalog.hypertable h,
_timescaledb_catalog.chunk c,
_timescaledb_catalog.chunk_constraint cc,
_timescaledb_catalog.dimension d,
_timescaledb_catalog.dimension_slice ds,
pg_class pgc,
pg_namespace pns
WHERE h.schema_name = %L
AND h.table_name = %L
AND pgc.relname = h.table_name
AND pns.oid = pgc.relnamespace
AND pns.nspname = h.schema_name
AND relkind = 'r'
AND c.hypertable_id = h.id
AND c.id = cc.chunk_id
AND cc.dimension_slice_id = ds.id
AND ds.dimension_id = d.id
GROUP BY c.id, pgc.reltoastrelid, pgc.oid ORDER BY c.id
) sub1
) sub2;
$$,
schema_name, table_name);
END;
$BODY$;
-- Get relation size of the chunks of an hypertable
-- like pg_relation_size
-- (https://www.postgresql.org/docs/9.6/static/functions-admin.html#FUNCTIONS-ADMIN-DBSIZE)
--
-- main_table - hypertable to get size of
--
-- Returns:
-- chunk_id - Timescaledb id of a chunk
-- chunk_table - Table used for the chunk
-- partitioning_columns - Partitioning column names
-- partitioning_column_types - Type of partitioning columns
-- partitioning_hash_functions - Hash functions of partitioning columns
-- ranges - Partition ranges for each dimension of the chunk
-- table_size - Pretty output of table_bytes
-- index_size - Pretty output of index_bytes
-- toast_size - Pretty output of toast_bytes
-- total_size - Pretty output of total_bytes
CREATE OR REPLACE FUNCTION chunk_relation_size_pretty(
main_table REGCLASS
)
RETURNS TABLE (chunk_id INT,
chunk_table TEXT,
partitioning_columns NAME[],
partitioning_column_types REGTYPE[],
partitioning_hash_functions TEXT[],
ranges TEXT[],
table_size TEXT,
index_size TEXT,
toast_size TEXT,
total_size TEXT
)
LANGUAGE PLPGSQL STABLE
AS
$BODY$
DECLARE
table_name NAME;
schema_name NAME;
BEGIN
SELECT relname, nspname
INTO STRICT table_name, schema_name
FROM pg_class c
INNER JOIN pg_namespace n ON (n.OID = c.relnamespace)
WHERE c.OID = main_table;
RETURN QUERY EXECUTE format(
$$
SELECT chunk_id,
chunk_table,
partitioning_columns,
partitioning_column_types,
partitioning_functions,
ranges,
pg_size_pretty(table_bytes) AS table,
pg_size_pretty(index_bytes) AS index,
pg_size_pretty(toast_bytes) AS toast,
pg_size_pretty(total_bytes) AS total
FROM (
SELECT *,
total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes
FROM (
SELECT c.id as chunk_id,
'"' || c.schema_name || '"."' || c.table_name || '"' as chunk_table,
pg_total_relation_size('"' || c.schema_name || '"."' || c.table_name || '"') AS total_bytes,
pg_indexes_size('"' || c.schema_name || '"."' || c.table_name || '"') AS index_bytes,
pg_total_relation_size(reltoastrelid) AS toast_bytes,
array_agg(d.column_name ORDER BY d.interval_length, d.column_name ASC) as partitioning_columns,
array_agg(d.column_type ORDER BY d.interval_length, d.column_name ASC) as partitioning_column_types,
array_agg(d.partitioning_func_schema || '.' || d.partitioning_func ORDER BY d.interval_length, d.column_name ASC) as partitioning_functions,
array_agg('[' || _timescaledb_internal.range_value_to_pretty(range_start, column_type) ||
',' ||
_timescaledb_internal.range_value_to_pretty(range_end, column_type) || ')' ORDER BY d.interval_length, d.column_name ASC) as ranges
FROM
_timescaledb_catalog.hypertable h,
_timescaledb_catalog.chunk c,
_timescaledb_catalog.chunk_constraint cc,
_timescaledb_catalog.dimension d,
_timescaledb_catalog.dimension_slice ds,
pg_class pgc,
pg_namespace pns
WHERE h.schema_name = %L
AND h.table_name = %L
AND pgc.relname = h.table_name
AND pns.oid = pgc.relnamespace
AND pns.nspname = h.schema_name
AND relkind = 'r'
AND c.hypertable_id = h.id
AND c.id = cc.chunk_id
AND cc.dimension_slice_id = ds.id
AND ds.dimension_id = d.id
GROUP BY c.id, pgc.reltoastrelid, pgc.oid ORDER BY c.id
) sub1
) sub2;
$$,
schema_name, table_name);
END;
$BODY$;
-- Get sizes of indexes on a hypertable
--
-- main_table - hypertable to get index sizes of
--
-- Returns:
-- index_name - index on hyper table
-- total_bytes - size of index on disk
CREATE OR REPLACE FUNCTION indexes_relation_size(
main_table REGCLASS
)
RETURNS TABLE (index_name TEXT,
total_bytes BIGINT)
LANGUAGE PLPGSQL STABLE
AS
$BODY$
<<main>>
DECLARE
table_name NAME;
schema_name NAME;
BEGIN
SELECT relname, nspname
INTO STRICT table_name, schema_name
FROM pg_class c
INNER JOIN pg_namespace n ON (n.OID = c.relnamespace)
WHERE c.OID = main_table;
RETURN QUERY
SELECT h.schema_name || '.' || ci.hypertable_index_name,
sum(pg_relation_size(c.oid))::bigint
FROM
pg_class c,
pg_namespace n,
_timescaledb_catalog.hypertable h,
_timescaledb_catalog.chunk ch,
_timescaledb_catalog.chunk_index ci
WHERE ch.schema_name = n.nspname
AND c.relnamespace = n.oid
AND c.relname = ci.index_name
AND ch.id = ci.chunk_id
AND h.id = ci.hypertable_id
AND h.schema_name = main.schema_name
AND h.table_name = main.table_name
GROUP BY h.schema_name, ci.hypertable_index_name;
END;
$BODY$;
-- Get sizes of indexes on a hypertable
--
-- main_table - hypertable to get index sizes of
--
-- Returns:
-- index_name - index on hyper table
-- total_size - pretty output of total_bytes
CREATE OR REPLACE FUNCTION indexes_relation_size_pretty(
main_table REGCLASS
)
RETURNS TABLE (index_name TEXT,
total_size TEXT) LANGUAGE PLPGSQL STABLE
AS
$BODY$
BEGIN
RETURN QUERY
SELECT s.index_name,
pg_size_pretty(s.total_bytes)
FROM indexes_relation_size(main_table) s;
END;
$BODY$;