Start version 4.2.1 to fix a bug in 4.1.4--4.2.0 upgrade script.

The upgrade script unfortunately didn't account for existing records in the
various tables where the new NOT NULL toplevel field was added, making it
impossible to upgrade the extension if a snapshot has been taken already.

Introduce a new 4.2.1 version which is strictly identical with version 4.2.0,
but with an upgrade script from 4.1.4 to 4.2.1 on top of a normal (and empty)
4.2.0 to 4.2.1 upgrade script.

The direct upgrade script will be chosen in priority by postgres, so people
still in 4.1.4 will be able to upgrade.  Also allow anyone with 4.2.0 installed
can upgrade to this new version, either now or automatically when the next
version will be released.

powa--4.1.4--4.2.1.sql

@@ -0,0 +1,342 @@
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "ALTER EXTENSION powa" to load this file. \quit
+
+SET LOCAL statement_timeout = 0;
+SET LOCAL client_encoding = 'UTF8';
+SET LOCAL standard_conforming_strings = on;
+SET LOCAL client_min_messages = warning;
+SET LOCAL search_path = public, pg_catalog;
+
+ALTER TABLE public.powa_statements_src_tmp ADD toplevel boolean;
+UPDATE public.powa_statements_src_tmp SET toplevel = true;
+ALTER TABLE public.powa_statements_src_tmp ALTER COLUMN toplevel SET NOT NULL;
+
+ALTER TABLE public.powa_statements_history ADD toplevel boolean;
+UPDATE public.powa_statements_history SET toplevel = true;
+ALTER TABLE public.powa_statements_history ALTER COLUMN toplevel SET NOT NULL;
+
+ALTER TABLE public.powa_statements_history_current ADD toplevel boolean;
+UPDATE public.powa_statements_history_current SET toplevel = true;
+ALTER TABLE public.powa_statements_history_current ALTER COLUMN toplevel SET NOT NULL;
+
+DROP FUNCTION powa_statements_src(integer);
+CREATE OR REPLACE FUNCTION powa_statements_src(IN _srvid integer,
+    OUT ts timestamp with time zone,
+    OUT userid oid,
+    OUT dbid oid,
+    OUT toplevel boolean,
+    OUT queryid bigint,
+    OUT query text,
+    OUT calls bigint,
+    OUT total_exec_time double precision,
+    OUT rows bigint,
+    OUT shared_blks_hit bigint,
+    OUT shared_blks_read bigint,
+    OUT shared_blks_dirtied bigint,
+    OUT shared_blks_written bigint,
+    OUT local_blks_hit bigint,
+    OUT local_blks_read bigint,
+    OUT local_blks_dirtied bigint,
+    OUT local_blks_written bigint,
+    OUT temp_blks_read bigint,
+    OUT temp_blks_written bigint,
+    OUT blk_read_time double precision,
+    OUT blk_write_time double precision,
+    OUT plans bigint,
+    OUT total_plan_time float8,
+    OUT wal_records bigint,
+    OUT wal_fpi bigint,
+    OUT wal_bytes numeric
+)
+RETURNS SETOF record
+STABLE
+AS $PROC$
+DECLARE
+    v_pgss integer[];
+BEGIN
+    IF (_srvid = 0) THEN
+        SELECT regexp_split_to_array(extversion, E'\\.') INTO STRICT v_pgss
+        FROM pg_extension
+        WHERE extname = 'pg_stat_statements';
+
+        IF (v_pgss[1] = 1 AND v_pgss[2] >= 10) THEN
+            RETURN QUERY SELECT now(),
+                pgss.userid, pgss.dbid, pgss.toplevel, pgss.queryid, pgss.query,
+                pgss.calls, pgss.total_exec_time,
+                pgss.rows, pgss.shared_blks_hit,
+                pgss.shared_blks_read, pgss.shared_blks_dirtied,
+                pgss.shared_blks_written, pgss.local_blks_hit,
+                pgss.local_blks_read, pgss.local_blks_dirtied,
+                pgss.local_blks_written, pgss.temp_blks_read,
+                pgss.temp_blks_written, pgss.blk_read_time, pgss.blk_write_time,
+                pgss.plans, pgss.total_plan_time,
+                pgss.wal_records, pgss.wal_fpi, pgss.wal_bytes
+            FROM pg_stat_statements pgss
+            JOIN pg_database d ON d.oid = pgss.dbid
+            JOIN pg_roles r ON pgss.userid = r.oid
+            WHERE pgss.query !~* '^[[:space:]]*(DEALLOCATE|BEGIN|PREPARE TRANSACTION|COMMIT PREPARED|ROLLBACK PREPARED)'
+            AND NOT (r.rolname = ANY (string_to_array(
+                        powa_get_guc('powa.ignored_users', ''),
+                        ',')));
+        ELSIF (v_pgss[1] = 1 AND v_pgss[2] >= 8) THEN
+            RETURN QUERY SELECT now(),
+                pgss.userid, pgss.dbid, true::boolean, pgss.queryid, pgss.query,
+                pgss.calls, pgss.total_exec_time,
+                pgss.rows, pgss.shared_blks_hit,
+                pgss.shared_blks_read, pgss.shared_blks_dirtied,
+                pgss.shared_blks_written, pgss.local_blks_hit,
+                pgss.local_blks_read, pgss.local_blks_dirtied,
+                pgss.local_blks_written, pgss.temp_blks_read,
+                pgss.temp_blks_written, pgss.blk_read_time, pgss.blk_write_time,
+                pgss.plans, pgss.total_plan_time,
+                pgss.wal_records, pgss.wal_fpi, pgss.wal_bytes
+            FROM pg_stat_statements pgss
+            JOIN pg_database d ON d.oid = pgss.dbid
+            JOIN pg_roles r ON pgss.userid = r.oid
+            WHERE pgss.query !~* '^[[:space:]]*(DEALLOCATE|BEGIN|PREPARE TRANSACTION|COMMIT PREPARED|ROLLBACK PREPARED)'
+            AND NOT (r.rolname = ANY (string_to_array(
+                        powa_get_guc('powa.ignored_users', ''),
+                        ',')));
+        ELSE
+            RETURN QUERY SELECT now(),
+                pgss.userid, pgss.dbid, true::boolean, pgss.queryid, pgss.query,
+                pgss.calls, pgss.total_time,
+                pgss.rows, pgss.shared_blks_hit,
+                pgss.shared_blks_read, pgss.shared_blks_dirtied,
+                pgss.shared_blks_written, pgss.local_blks_hit,
+                pgss.local_blks_read, pgss.local_blks_dirtied,
+                pgss.local_blks_written, pgss.temp_blks_read,
+                pgss.temp_blks_written, pgss.blk_read_time,pgss.blk_write_time,
+                0::bigint, 0::double precision,
+                0::bigint, 0::bigint, 0::numeric
+
+            FROM pg_stat_statements pgss
+            JOIN pg_database d ON d.oid = pgss.dbid
+            JOIN pg_roles r ON pgss.userid = r.oid
+            WHERE pgss.query !~* '^[[:space:]]*(DEALLOCATE|BEGIN|PREPARE TRANSACTION|COMMIT PREPARED|ROLLBACK PREPARED)'
+            AND NOT (r.rolname = ANY (string_to_array(
+                        powa_get_guc('powa.ignored_users', ''),
+                        ',')));
+        END IF;
+    ELSE
+        RETURN QUERY SELECT pgss.ts,
+            pgss.userid, pgss.dbid, pgss.toplevel, pgss.queryid, pgss.query,
+            pgss.calls, pgss.total_exec_time,
+            pgss.rows, pgss.shared_blks_hit,
+            pgss.shared_blks_read, pgss.shared_blks_dirtied,
+            pgss.shared_blks_written, pgss.local_blks_hit,
+            pgss.local_blks_read, pgss.local_blks_dirtied,
+            pgss.local_blks_written, pgss.temp_blks_read,
+            pgss.temp_blks_written, pgss.blk_read_time, pgss.blk_write_time,
+            pgss.plans, pgss.total_plan_time,
+            pgss.wal_records, pgss.wal_fpi, pgss.wal_bytes
+        FROM powa_statements_src_tmp pgss WHERE srvid = _srvid;
+    END IF;
+END;
+$PROC$ LANGUAGE plpgsql; /* end of powa_statements_src */
+
+CREATE OR REPLACE FUNCTION powa_statements_snapshot(_srvid integer) RETURNS void AS $PROC$
+DECLARE
+    result boolean;
+    v_funcname    text := 'powa_statements_snapshot';
+    v_rowcount    bigint;
+BEGIN
+    -- In this function, we capture statements, and also aggregate counters by database
+    -- so that the first screens of powa stay reactive even though there may be thousands
+    -- of different statements
+    -- We only capture databases that are still there
+    PERFORM powa_log(format('running %I', v_funcname));
+
+    PERFORM powa_prevent_concurrent_snapshot(_srvid);
+
+    WITH capture AS(
+        SELECT *
+        FROM powa_statements_src(_srvid)
+    ),
+    mru as (UPDATE powa_statements set last_present_ts = now()
+            FROM capture
+            WHERE powa_statements.queryid = capture.queryid
+              AND powa_statements.dbid = capture.dbid
+              AND powa_statements.userid = capture.userid
+              AND powa_statements.srvid = _srvid
+    ),
+    missing_statements AS(
+        INSERT INTO public.powa_statements (srvid, queryid, dbid, userid, query)
+            SELECT _srvid, queryid, dbid, userid, min(query)
+            FROM capture c
+            WHERE NOT EXISTS (SELECT 1
+                              FROM powa_statements ps
+                              WHERE ps.queryid = c.queryid
+                              AND ps.dbid = c.dbid
+                              AND ps.userid = c.userid
+                              AND ps.srvid = _srvid
+            )
+            GROUP BY queryid, dbid, userid
+    ),
+
+    by_query AS (
+        INSERT INTO public.powa_statements_history_current (srvid, queryid,
+                dbid, toplevel, userid, record)
+            SELECT _srvid, queryid, dbid, toplevel, userid,
+            ROW(
+                ts, calls, total_exec_time, rows,
+                shared_blks_hit, shared_blks_read, shared_blks_dirtied,
+                shared_blks_written, local_blks_hit, local_blks_read,
+                local_blks_dirtied, local_blks_written, temp_blks_read,
+                temp_blks_written, blk_read_time, blk_write_time,
+                plans, total_plan_time,
+                wal_records, wal_fpi, wal_bytes
+            )::powa_statements_history_record AS record
+            FROM capture
+    ),
+
+    by_database AS (
+        INSERT INTO public.powa_statements_history_current_db (srvid, dbid, record)
+            SELECT _srvid, dbid,
+            ROW(
+                ts, sum(calls),
+                sum(total_exec_time), sum(rows), sum(shared_blks_hit),
+                sum(shared_blks_read), sum(shared_blks_dirtied),
+                sum(shared_blks_written), sum(local_blks_hit),
+                sum(local_blks_read), sum(local_blks_dirtied),
+                sum(local_blks_written), sum(temp_blks_read),
+                sum(temp_blks_written), sum(blk_read_time), sum(blk_write_time),
+                sum(plans), sum(total_plan_time),
+                sum(wal_records), sum(wal_fpi), sum(wal_bytes)
+            )::powa_statements_history_record AS record
+            FROM capture
+            GROUP BY dbid, ts
+    )
+
+    SELECT count(*) INTO v_rowcount
+    FROM capture;
+
+    perform powa_log(format('%I - rowcount: %s',
+            v_funcname, v_rowcount));
+
+    IF (_srvid != 0) THEN
+        DELETE FROM powa_statements_src_tmp WHERE srvid = _srvid;
+    END IF;
+
+    result := true; -- For now we don't care. What could we do on error except crash anyway?
+END;
+$PROC$ language plpgsql; /* end of powa_statements_snapshot */
+
+CREATE OR REPLACE FUNCTION powa_statements_aggregate(_srvid integer)
+RETURNS void AS $PROC$
+DECLARE
+    v_funcname    text := 'powa_statements_aggregate(' || _srvid || ')';
+    v_rowcount    bigint;
+BEGIN
+    PERFORM powa_log(format('running %I', v_funcname));
+
+    PERFORM powa_prevent_concurrent_snapshot(_srvid);
+
+    -- aggregate statements table
+    INSERT INTO public.powa_statements_history (srvid, queryid, dbid, toplevel,
+            userid, coalesce_range, records, mins_in_range, maxs_in_range)
+        SELECT srvid, queryid, dbid, toplevel, userid,
+            tstzrange(min((record).ts), max((record).ts),'[]'),
+            array_agg(record),
+            ROW(min((record).ts),
+                min((record).calls),min((record).total_exec_time),
+                min((record).rows),
+                min((record).shared_blks_hit),min((record).shared_blks_read),
+                min((record).shared_blks_dirtied),min((record).shared_blks_written),
+                min((record).local_blks_hit),min((record).local_blks_read),
+                min((record).local_blks_dirtied),min((record).local_blks_written),
+                min((record).temp_blks_read),min((record).temp_blks_written),
+                min((record).blk_read_time),min((record).blk_write_time),
+                min((record).plans),min((record).total_plan_time),
+                min((record).wal_records),min((record).wal_fpi),
+                min((record).wal_bytes)
+            )::powa_statements_history_record,
+            ROW(max((record).ts),
+                max((record).calls),max((record).total_exec_time),
+                max((record).rows),
+                max((record).shared_blks_hit),max((record).shared_blks_read),
+                max((record).shared_blks_dirtied),max((record).shared_blks_written),
+                max((record).local_blks_hit),max((record).local_blks_read),
+                max((record).local_blks_dirtied),max((record).local_blks_written),
+                max((record).temp_blks_read),max((record).temp_blks_written),
+                max((record).blk_read_time),max((record).blk_write_time),
+                max((record).plans),max((record).total_plan_time),
+                max((record).wal_records),max((record).wal_fpi),
+                max((record).wal_bytes)
+            )::powa_statements_history_record
+        FROM powa_statements_history_current
+        WHERE srvid = _srvid
+        GROUP BY srvid, queryid, dbid, toplevel, userid;
+
+    GET DIAGNOSTICS v_rowcount = ROW_COUNT;
+    perform powa_log(format('%I (powa_statements_history) - rowcount: %s',
+            v_funcname, v_rowcount));
+
+    DELETE FROM powa_statements_history_current WHERE srvid = _srvid;
+
+    -- aggregate db table
+    INSERT INTO public.powa_statements_history_db (srvid, dbid, coalesce_range,
+            records, mins_in_range, maxs_in_range)
+        SELECT srvid, dbid,
+            tstzrange(min((record).ts), max((record).ts),'[]'),
+            array_agg(record),
+            ROW(min((record).ts),
+                min((record).calls),min((record).total_exec_time),
+                min((record).rows),
+                min((record).shared_blks_hit),min((record).shared_blks_read),
+                min((record).shared_blks_dirtied),min((record).shared_blks_written),
+                min((record).local_blks_hit),min((record).local_blks_read),
+                min((record).local_blks_dirtied),min((record).local_blks_written),
+                min((record).temp_blks_read),min((record).temp_blks_written),
+                min((record).blk_read_time),min((record).blk_write_time),
+                min((record).plans),min((record).total_plan_time),
+                min((record).wal_records),min((record).wal_fpi),
+                min((record).wal_bytes)
+            )::powa_statements_history_record,
+            ROW(max((record).ts),
+                max((record).calls),max((record).total_exec_time),
+                max((record).rows),
+                max((record).shared_blks_hit),max((record).shared_blks_read),
+                max((record).shared_blks_dirtied),max((record).shared_blks_written),
+                max((record).local_blks_hit),max((record).local_blks_read),
+                max((record).local_blks_dirtied),max((record).local_blks_written),
+                max((record).temp_blks_read),max((record).temp_blks_written),
+                max((record).blk_read_time),max((record).blk_write_time),
+                max((record).plans),max((record).total_plan_time),
+                max((record).wal_records),max((record).wal_fpi),
+                max((record).wal_bytes)
+            )::powa_statements_history_record
+        FROM powa_statements_history_current_db
+        WHERE srvid = _srvid
+        GROUP BY srvid, dbid;
+
+    GET DIAGNOSTICS v_rowcount = ROW_COUNT;
+    perform powa_log(format('%I (powa_statements_history_db) - rowcount: %s',
+            v_funcname, v_rowcount));
+
+    DELETE FROM powa_statements_history_current_db WHERE srvid = _srvid;
+END;
+$PROC$ LANGUAGE plpgsql; /* end of powa_statements_aggregate */
+
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_reads DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_writes DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_user_time DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_system_time DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_minflts DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_majflts DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_nswaps DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_msgsnds DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_msgrcvs DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_nsignals DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_nvcsws DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN plan_nivcsws DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_reads DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_writes DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_minflts DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_majflts DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_nswaps DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_msgsnds DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_msgrcvs DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_nsignals DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_nvcsws DROP NOT NULL;
+ALTER TABLE public.powa_kcache_src_tmp ALTER COLUMN exec_nivcsws DROP NOT NULL;

powa--4.2.0--4.2.1.sql

@@ -0,0 +1,5 @@
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "ALTER EXTENSION powa" to load this file. \quit
+
+-- Nothing to do, 4.2.0 and 4.2.1 are identical, the new version was only
+-- needed to fix a bug with the 4.1.4 <-> 4.2.0 upgrade script.