create_partition_time.sql

CREATE FUNCTION @extschema@.create_partition_time(p_parent_table text, p_partition_times timestamptz[], p_analyze boolean DEFAULT true, p_start_partition text DEFAULT NULL) 
RETURNS boolean
    LANGUAGE plpgsql
    AS $$
DECLARE

ex_context                      text;
ex_detail                       text;
ex_hint                         text;
ex_message                      text;
v_all                           text[] := ARRAY['SELECT', 'INSERT', 'UPDATE', 'DELETE', 'TRUNCATE', 'REFERENCES', 'TRIGGER'];
v_analyze                       boolean := FALSE;
v_control                       text;
v_control_type                  text;
v_datetime_string               text;
v_epoch                         text;
v_exists                        smallint;
v_grantees                      text[];
v_hasoids                       boolean;
v_inherit_privileges            boolean;
v_inherit_fk                    boolean;
v_job_id                        bigint;
v_jobmon                        boolean;
v_jobmon_schema                 text;
v_new_search_path               text;
v_old_search_path               text;
v_parent_grant                  record;
v_parent_schema                 text;
v_parent_tablename              text;
v_part_col                      text;
v_partition_created             boolean := false;
v_partition_name                text;
v_partition_suffix              text;
v_parent_tablespace             text;
v_partition_expression          text;
v_partition_interval            interval;
v_partition_timestamp_end       timestamptz;
v_partition_timestamp_start     timestamptz;
v_publications                  text[];
v_quarter                       text;
v_revoke                        text;
v_row                           record;
v_sql                           text;
v_step_id                       bigint;
v_step_overflow_id              bigint;
v_sub_control                   text;
v_sub_parent                    text;
v_sub_partition_type            text;
v_sub_timestamp_max             timestamptz;
v_sub_timestamp_min             timestamptz;
v_template_table                text;
v_trunc_value                   text;
v_time                          timestamptz;
v_partition_type                          text;
v_unlogged                      char;
v_year                          text;

BEGIN
/*
 * Function to create a child table in a time-based partition set
 */

SELECT partition_type
    , control
    , partition_interval
    , epoch
    , inherit_fk
    , jobmon
    , datetime_string
    , template_table
    , publications
    , inherit_privileges
INTO v_partition_type
    , v_control
    , v_partition_interval
    , v_epoch
    , v_inherit_fk
    , v_jobmon
    , v_datetime_string
    , v_template_table
    , v_publications
    , v_inherit_privileges
FROM @extschema@.part_config
WHERE parent_table = p_parent_table;

IF NOT FOUND THEN
    RAISE EXCEPTION 'ERROR: no config found for %', p_parent_table;
END IF;

SELECT n.nspname, c.relname, t.spcname 
INTO v_parent_schema, v_parent_tablename, v_parent_tablespace 
FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON c.relnamespace = n.oid
LEFT OUTER JOIN pg_catalog.pg_tablespace t ON c.reltablespace = t.oid
WHERE n.nspname = split_part(p_parent_table, '.', 1)::name
AND c.relname = split_part(p_parent_table, '.', 2)::name;

SELECT general_type INTO v_control_type FROM @extschema@.check_control_type(v_parent_schema, v_parent_tablename, v_control);
IF v_control_type <> 'time' THEN 
    IF (v_control_type = 'id' AND v_epoch = 'none') OR v_control_type <> 'id' THEN
        RAISE EXCEPTION 'Cannot run on partition set without time based control column or epoch flag set with an id column. Found control: %, epoch: %', v_control_type, v_epoch;
    END IF;
END IF;

SELECT current_setting('search_path') INTO v_old_search_path;
IF length(v_old_search_path) > 0 THEN
   v_new_search_path := '@extschema@,pg_temp,'||v_old_search_path;
ELSE
    v_new_search_path := '@extschema@,pg_temp';
END IF;
IF v_jobmon THEN
    SELECT nspname INTO v_jobmon_schema FROM pg_catalog.pg_namespace n, pg_catalog.pg_extension e WHERE e.extname = 'pg_jobmon'::name AND e.extnamespace = n.oid;
    IF v_jobmon_schema IS NOT NULL THEN
        v_new_search_path := format('%s,%s',v_jobmon_schema, v_new_search_path);
    END IF;
END IF;
EXECUTE format('SELECT set_config(%L, %L, %L)', 'search_path', v_new_search_path, 'false');

-- Determine if this table is a child of a subpartition parent. If so, get limits of what child tables can be created based on parent suffix
SELECT sub_min::timestamptz, sub_max::timestamptz INTO v_sub_timestamp_min, v_sub_timestamp_max FROM @extschema@.check_subpartition_limits(p_parent_table, 'time');

IF v_jobmon_schema IS NOT NULL THEN
    v_job_id := add_job(format('PARTMAN CREATE TABLE: %s', p_parent_table));
END IF;

v_partition_expression := CASE
    WHEN v_epoch = 'seconds' THEN format('to_timestamp(%I)', v_control)
    WHEN v_epoch = 'milliseconds' THEN format('to_timestamp((%I/1000)::float)', v_control)
    WHEN v_epoch = 'nanoseconds' THEN format('to_timestamp((%I/1000000000)::float)', v_control)
    ELSE format('%I', v_control)
END;
RAISE DEBUG 'create_partition_time: v_partition_expression: %', v_partition_expression;

FOREACH v_time IN ARRAY p_partition_times LOOP    
    v_partition_timestamp_start := v_time;
    BEGIN
        v_partition_timestamp_end := v_time + v_partition_interval;
    EXCEPTION WHEN datetime_field_overflow THEN
        RAISE WARNING 'Attempted partition time interval is outside PostgreSQL''s supported time range. 
            Child partition creation after time % skipped', v_time;
        v_step_overflow_id := add_step(v_job_id, 'Attempted partition time interval is outside PostgreSQL''s supported time range.');
        PERFORM update_step(v_step_overflow_id, 'CRITICAL', 'Child partition creation after time '||v_time||' skipped');

        CONTINUE;
    END;

    -- Do not create the child table if it's outside the bounds of the top parent. 
    IF v_sub_timestamp_min IS NOT NULL THEN
        IF v_time < v_sub_timestamp_min OR v_time >= v_sub_timestamp_max THEN

            RAISE DEBUG 'create_partition_time: p_parent_table: %, v_time: %, v_sub_timestamp_min: %, v_sub_timestamp_max: %'
                    , p_parent_table, v_time, v_sub_timestamp_min, v_sub_timestamp_max;

            CONTINUE;
        END IF;
    END IF;

    -- This suffix generation code is in partition_data_time() as well
    v_partition_suffix := to_char(v_time, v_datetime_string);
    v_partition_name := @extschema@.check_name_length(v_parent_tablename, v_partition_suffix, TRUE);
    -- Check if child exists. 
    SELECT count(*) INTO v_exists
    FROM pg_catalog.pg_class c
    JOIN pg_catalog.pg_namespace n ON c.relnamespace = n.oid
    WHERE n.nspname = v_parent_schema::name 
    AND c.relname = v_partition_name::name;

    IF v_exists > 0 THEN
        CONTINUE;
    END IF;

    -- Ensure analyze is run if a new partition is created. Otherwise if one isn't, will be false and analyze will be skipped
    v_analyze := TRUE;

    IF v_jobmon_schema IS NOT NULL THEN
        v_step_id := add_step(v_job_id, format('Creating new partition %s.%s with interval from %s to %s'
                                                , v_parent_schema
                                                , v_partition_name
                                                , v_partition_timestamp_start
                                                , v_partition_timestamp_end-'1sec'::interval));
    END IF;

    v_sql := 'CREATE';

    -- As of PG12, the unlogged/logged status of a native parent table cannot be changed via an ALTER TABLE in order to affect its children.
    -- As of v4.2x, the unlogged state will be managed via the template table    
    SELECT relpersistence INTO v_unlogged 
    FROM pg_catalog.pg_class c
    JOIN pg_catalog.pg_namespace n ON c.relnamespace = n.oid
    WHERE c.relname = v_parent_tablename::name
    AND n.nspname = v_parent_schema::name;
    IF v_unlogged = 'u' and v_partition_type != 'native'  THEN
        v_sql := v_sql || ' UNLOGGED';
    END IF;

    -- Close parentheses on LIKE are below due to differing requirements of native subpartitioning
    -- Same INCLUDING list is used in create_parent()
    v_sql := v_sql || format(' TABLE %I.%I (LIKE %I.%I INCLUDING DEFAULTS INCLUDING CONSTRAINTS INCLUDING STORAGE INCLUDING COMMENTS '
                                , v_parent_schema
                                , v_partition_name
                                , v_parent_schema
                                , v_parent_tablename);

    IF current_setting('server_version_num')::int >= 120000 THEN
        v_sql := v_sql || ' INCLUDING GENERATED ';
    END IF;


    SELECT sub_partition_type, sub_control INTO v_sub_partition_type, v_sub_control 
    FROM @extschema@.part_config_sub 
    WHERE sub_parent = p_parent_table;
    IF v_sub_partition_type = 'native' THEN
        -- INCLUDING INDEXES isn't necessary for native partitioning. It isn't supported in v10 and 
	--   for v11+ index inheritance is automatically handled when the partition is attached
        v_sql := v_sql || format(') PARTITION BY RANGE (%I) ', v_sub_control);
    ELSE
        v_sql := v_sql || format(' INCLUDING INDEXES) ');
    END IF;

    IF current_setting('server_version_num')::int < 120000 THEN
        -- column removed from pgclass in pg12
        SELECT relhasoids INTO v_hasoids 
        FROM pg_catalog.pg_class c
        JOIN pg_catalog.pg_namespace n ON c.relnamespace = n.oid
        WHERE c.relname = v_parent_tablename::name
        AND n.nspname = v_parent_schema::name;
        IF v_hasoids IS TRUE THEN
            v_sql := v_sql || ' WITH (OIDS)';
        END IF;
    END IF;

    RAISE DEBUG 'create_partition_time v_sql: %', v_sql;
    EXECUTE v_sql;


    IF v_partition_type = 'native' THEN

        IF current_setting('server_version_num')::int >= 120000 THEN
            -- PG12 fixed tablespace marking on the parent of a native partition set
            -- Versions older than 12 handle tablespace setting via inherit_template_properties() call below
            IF v_parent_tablespace IS NOT NULL THEN
                EXECUTE format('ALTER TABLE %I.%I SET TABLESPACE %I', v_parent_schema, v_partition_name, v_parent_tablespace);
            END IF;
        END IF;

        IF v_template_table IS NOT NULL THEN
            PERFORM @extschema@.inherit_template_properties(p_parent_table, v_parent_schema, v_partition_name);
        END IF;

        IF v_epoch = 'none' THEN
            -- Attach with normal, time-based values for native constraint
            EXECUTE format('ALTER TABLE %I.%I ATTACH PARTITION %I.%I FOR VALUES FROM (%L) TO (%L)'
                , v_parent_schema
                , v_parent_tablename
                , v_parent_schema
                , v_partition_name
                , v_partition_timestamp_start
                , v_partition_timestamp_end);
        ELSE
            -- Must attach with integer based values for native constraint and epoch
            IF v_epoch = 'seconds' THEN
                EXECUTE format('ALTER TABLE %I.%I ATTACH PARTITION %I.%I FOR VALUES FROM (%L) TO (%L)'
                    , v_parent_schema
                    , v_parent_tablename
                    , v_parent_schema
                    , v_partition_name
                    , EXTRACT('epoch' FROM v_partition_timestamp_start)::bigint
                    , EXTRACT('epoch' FROM v_partition_timestamp_end)::bigint);
            ELSIF v_epoch = 'milliseconds' THEN
                EXECUTE format('ALTER TABLE %I.%I ATTACH PARTITION %I.%I FOR VALUES FROM (%L) TO (%L)'
                    , v_parent_schema
                    , v_parent_tablename
                    , v_parent_schema
                    , v_partition_name
                    , EXTRACT('epoch' FROM v_partition_timestamp_start)::bigint * 1000
                    , EXTRACT('epoch' FROM v_partition_timestamp_end)::bigint * 1000);
            ELSIF v_epoch = 'nanoseconds' THEN
                EXECUTE format('ALTER TABLE %I.%I ATTACH PARTITION %I.%I FOR VALUES FROM (%L) TO (%L)'
                    , v_parent_schema
                    , v_parent_tablename
                    , v_parent_schema
                    , v_partition_name
                    , EXTRACT('epoch' FROM v_partition_timestamp_start)::bigint * 1000000000
                    , EXTRACT('epoch' FROM v_partition_timestamp_end)::bigint * 1000000000);
            END IF;
            -- Create secondary, time-based constraint since native's constraint is already integer based
            EXECUTE format('ALTER TABLE %I.%I ADD CONSTRAINT %I CHECK (%s >= %L AND %4$s < %6$L)'
                , v_parent_schema
                , v_partition_name
                , v_partition_name||'_partition_check'
                , v_partition_expression
                , v_partition_timestamp_start
                , v_partition_timestamp_end);
        END IF;
    ELSE -- non-native

        IF v_parent_tablespace IS NOT NULL THEN
            EXECUTE format('ALTER TABLE %I.%I SET TABLESPACE %I', v_parent_schema, v_partition_name, v_parent_tablespace);
        END IF;

        -- Non-native always gets time-based constraint
        EXECUTE format('ALTER TABLE %I.%I ADD CONSTRAINT %I CHECK (%s >= %L AND %4$s < %6$L)'
            , v_parent_schema
            , v_partition_name
            , v_partition_name||'_partition_check'
            , v_partition_expression
            , v_partition_timestamp_start
            , v_partition_timestamp_end);
        IF v_epoch = 'seconds' THEN
            -- Non-native needs secondary, integer based constraint for epoch
            EXECUTE format('ALTER TABLE %I.%I ADD CONSTRAINT %I CHECK (%I >= %L AND %I < %L)'
                            , v_parent_schema
                            , v_partition_name
                            , v_partition_name||'_partition_int_check'
                            , v_control
                            , EXTRACT('epoch' from v_partition_timestamp_start)::bigint
                            , v_control
                            , EXTRACT('epoch' from v_partition_timestamp_end)::bigint );
        ELSIF v_epoch = 'milliseconds' THEN
            EXECUTE format('ALTER TABLE %I.%I ADD CONSTRAINT %I CHECK (%I >= %L AND %I < %L)'
                            , v_parent_schema
                            , v_partition_name
                            , v_partition_name||'_partition_int_check'
                            , v_control
                            , EXTRACT('epoch' from v_partition_timestamp_start)::bigint * 1000
                            , v_control
                            , EXTRACT('epoch' from v_partition_timestamp_end)::bigint * 1000);
        ELSIF v_epoch = 'nanoseconds' THEN
            EXECUTE format('ALTER TABLE %I.%I ADD CONSTRAINT %I CHECK (%I >= %L AND %I < %L)'
                            , v_parent_schema
                            , v_partition_name
                            , v_partition_name||'_partition_int_check'
                            , v_control
                            , EXTRACT('epoch' from v_partition_timestamp_start)::bigint * 1000000000
                            , v_control
                            , EXTRACT('epoch' from v_partition_timestamp_end)::bigint * 1000000000);
        END IF;

        EXECUTE format('ALTER TABLE %I.%I INHERIT %I.%I'
                        , v_parent_schema
                        , v_partition_name
                        , v_parent_schema
                        , v_parent_tablename);

        -- If custom time, set extra config options.
        IF v_partition_type = 'time-custom' THEN
            INSERT INTO @extschema@.custom_time_partitions (parent_table, child_table, partition_range)
            VALUES ( p_parent_table, v_parent_schema||'.'||v_partition_name, tstzrange(v_partition_timestamp_start, v_partition_timestamp_end, '[)') );
        END IF;

        -- Indexes cannot be created on the parent, so clustering cannot be used for native yet.
        PERFORM @extschema@.apply_cluster(v_parent_schema, v_parent_tablename, v_parent_schema, v_partition_name);

        -- Foreign keys to other tables not supported in native
        IF v_inherit_fk THEN
            PERFORM @extschema@.apply_foreign_keys(p_parent_table, v_parent_schema||'.'||v_partition_name, v_job_id);
        END IF;

    END IF; -- end native check

    -- NOTE: Privileges not automatically inherited for native. Only do so if config flag is set
    IF v_partition_type != 'native' OR (v_partition_type = 'native' AND v_inherit_privileges = TRUE) THEN
        PERFORM @extschema@.apply_privileges(v_parent_schema, v_parent_tablename, v_parent_schema, v_partition_name, v_job_id);
    END IF;

    IF v_jobmon_schema IS NOT NULL THEN
        PERFORM update_step(v_step_id, 'OK', 'Done');
    END IF;

    -- Will only loop once and only if sub_partitioning is actually configured
    -- This seemed easier than assigning a bunch of variables then doing an IF condition
    -- This column list must be kept consistent between: 
    --   create_parent, check_subpart_sameconfig, create_partition_id, create_partition_time, dump_partitioned_table_definition, and table definition
    FOR v_row IN 
        SELECT sub_parent
            , sub_partition_type
            , sub_control
            , sub_partition_interval
            , sub_constraint_cols
            , sub_premake
            , sub_optimize_trigger
            , sub_optimize_constraint
            , sub_epoch
            , sub_inherit_fk
            , sub_retention
            , sub_retention_schema
            , sub_retention_keep_table
            , sub_retention_keep_index
            , sub_infinite_time_partitions
            , sub_automatic_maintenance
            , sub_jobmon
            , sub_trigger_exception_handling
            , sub_upsert
            , sub_trigger_return_null
            , sub_template_table
            , sub_inherit_privileges
            , sub_constraint_valid
            , sub_subscription_refresh
            , sub_date_trunc_interval
            , sub_ignore_default_data
        FROM @extschema@.part_config_sub
        WHERE sub_parent = p_parent_table
    LOOP
        IF v_jobmon_schema IS NOT NULL THEN
            v_step_id := add_step(v_job_id, format('Subpartitioning %s.%s', v_parent_schema, v_partition_name));
        END IF;
        v_sql := format('SELECT @extschema@.create_parent(
                 p_parent_table := %L
                , p_control := %L
                , p_type := %L
                , p_interval := %L
                , p_constraint_cols := %L
                , p_premake := %L
                , p_automatic_maintenance := %L
                , p_inherit_fk := %L
                , p_epoch := %L
                , p_template_table := %L
                , p_jobmon := %L
                , p_start_partition := %L
                , p_date_trunc_interval := %L )'
            , v_parent_schema||'.'||v_partition_name
            , v_row.sub_control
            , v_row.sub_partition_type
            , v_row.sub_partition_interval
            , v_row.sub_constraint_cols
            , v_row.sub_premake
            , v_row.sub_automatic_maintenance
            , v_row.sub_inherit_fk
            , v_row.sub_epoch
            , v_row.sub_template_table
            , v_row.sub_jobmon
            , p_start_partition
            , v_row.sub_date_trunc_interval);
        
        RAISE DEBUG 'create_partition_time (create_parent loop): %', v_sql;
        EXECUTE v_sql;

        UPDATE @extschema@.part_config SET 
            retention_schema = v_row.sub_retention_schema
            , retention_keep_table = v_row.sub_retention_keep_table
            , retention_keep_index = v_row.sub_retention_keep_index
            , optimize_trigger = v_row.sub_optimize_trigger
            , optimize_constraint = v_row.sub_optimize_constraint
            , infinite_time_partitions = v_row.sub_infinite_time_partitions
            , trigger_exception_handling = v_row.sub_trigger_exception_handling
            , upsert = v_row.sub_upsert
            , inherit_privileges = v_row.sub_inherit_privileges
            , trigger_return_null = v_row.sub_trigger_return_null
            , constraint_valid = v_row.sub_constraint_valid
            , subscription_refresh = v_row.sub_subscription_refresh
            , ignore_default_data = v_row.sub_ignore_default_data
        WHERE parent_table = v_parent_schema||'.'||v_partition_name;

    END LOOP; -- end sub partitioning LOOP

    -- Manage additonal constraints if set
    PERFORM @extschema@.apply_constraints(p_parent_table, p_job_id := v_job_id);

    IF v_publications IS NOT NULL THEN
        -- NOTE: Native publication inheritance is only supported on PG14+
        PERFORM @extschema@.apply_publications(p_parent_table, v_parent_schema, v_partition_name);
    END IF;

    v_partition_created := true;

END LOOP;
-- v_analyze is a local check if a new table is made.
-- p_analyze is a parameter to say whether to run the analyze at all. Used by create_parent() to avoid long exclusive lock or run_maintenence() to avoid long creation runs.
IF v_analyze AND p_analyze THEN
    IF v_jobmon_schema IS NOT NULL THEN
        v_step_id := add_step(v_job_id, format('Analyzing partition set: %s', p_parent_table));
    END IF;

    EXECUTE format('ANALYZE %I.%I', v_parent_schema, v_parent_tablename);

    IF v_jobmon_schema IS NOT NULL THEN
        PERFORM update_step(v_step_id, 'OK', 'Done');
    END IF;
END IF;

IF v_jobmon_schema IS NOT NULL THEN
    IF v_partition_created = false THEN
        v_step_id := add_step(v_job_id, format('No partitions created for partition set: %s. Attempted intervals: %s', p_parent_table, p_partition_times));
        PERFORM update_step(v_step_id, 'OK', 'Done');
    END IF;

    IF v_step_overflow_id IS NOT NULL THEN
        PERFORM fail_job(v_job_id);
    ELSE
        PERFORM close_job(v_job_id);
    END IF;
END IF;

EXECUTE format('SELECT set_config(%L, %L, %L)', 'search_path', v_old_search_path, 'false');

RETURN v_partition_created;

EXCEPTION
    WHEN OTHERS THEN
        GET STACKED DIAGNOSTICS ex_message = MESSAGE_TEXT,
                                ex_context = PG_EXCEPTION_CONTEXT,
                                ex_detail = PG_EXCEPTION_DETAIL,
                                ex_hint = PG_EXCEPTION_HINT;
        IF v_jobmon_schema IS NOT NULL THEN
            IF v_job_id IS NULL THEN
                EXECUTE format('SELECT %I.add_job(''PARTMAN CREATE TABLE: %s'')', v_jobmon_schema, p_parent_table) INTO v_job_id;
                EXECUTE format('SELECT %I.add_step(%s, ''EXCEPTION before job logging started'')', v_jobmon_schema, v_job_id, p_parent_table) INTO v_step_id;
            ELSIF v_step_id IS NULL THEN
                EXECUTE format('SELECT %I.add_step(%s, ''EXCEPTION before first step logged'')', v_jobmon_schema, v_job_id) INTO v_step_id;
            END IF;
            EXECUTE format('SELECT %I.update_step(%s, ''CRITICAL'', %L)', v_jobmon_schema, v_step_id, 'ERROR: '||coalesce(SQLERRM,'unknown'));
            EXECUTE format('SELECT %I.fail_job(%s)', v_jobmon_schema, v_job_id);
        END IF;
        RAISE EXCEPTION '%
CONTEXT: %
DETAIL: %
HINT: %', ex_message, ex_context, ex_detail, ex_hint;
END
$$;