Add MariaDB with DuckDB storage engine

mariadb-duckdb/benchmark.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+# Thin shim — actual flow is in ../lib/benchmark-common.sh.
+export BENCH_DOWNLOAD_SCRIPT="download-hits-tsv"
+export BENCH_DURABLE=yes
+export BENCH_RESTARTABLE=yes
+exec ../lib/benchmark-common.sh

mariadb-duckdb/check

@@ -0,0 +1,3 @@
+#!/bin/bash
+set -e
+sudo mariadb -e "SELECT 1" >/dev/null

mariadb-duckdb/create.sql

@@ -0,0 +1,109 @@
+CREATE TABLE hits
+(
+    WatchID BIGINT NOT NULL,
+    JavaEnable SMALLINT NOT NULL,
+    Title TEXT NOT NULL,
+    GoodEvent SMALLINT NOT NULL,
+    EventTime TIMESTAMP NOT NULL,
+    EventDate Date NOT NULL,
+    CounterID INTEGER NOT NULL,
+    ClientIP INTEGER NOT NULL,
+    RegionID INTEGER NOT NULL,
+    UserID BIGINT NOT NULL,
+    CounterClass SMALLINT NOT NULL,
+    OS SMALLINT NOT NULL,
+    UserAgent SMALLINT NOT NULL,
+    URL TEXT NOT NULL,
+    Referer TEXT NOT NULL,
+    IsRefresh SMALLINT NOT NULL,
+    RefererCategoryID SMALLINT NOT NULL,
+    RefererRegionID INTEGER NOT NULL,
+    URLCategoryID SMALLINT NOT NULL,
+    URLRegionID INTEGER NOT NULL,
+    ResolutionWidth SMALLINT NOT NULL,
+    ResolutionHeight SMALLINT NOT NULL,
+    ResolutionDepth SMALLINT NOT NULL,
+    FlashMajor SMALLINT NOT NULL,
+    FlashMinor SMALLINT NOT NULL,
+    FlashMinor2 TEXT NOT NULL,
+    NetMajor SMALLINT NOT NULL,
+    NetMinor SMALLINT NOT NULL,
+    UserAgentMajor SMALLINT NOT NULL,
+    UserAgentMinor VARCHAR(255) NOT NULL,
+    CookieEnable SMALLINT NOT NULL,
+    JavascriptEnable SMALLINT NOT NULL,
+    IsMobile SMALLINT NOT NULL,
+    MobilePhone SMALLINT NOT NULL,
+    MobilePhoneModel TEXT NOT NULL,
+    Params TEXT NOT NULL,
+    IPNetworkID INTEGER NOT NULL,
+    TraficSourceID SMALLINT NOT NULL,
+    SearchEngineID SMALLINT NOT NULL,
+    SearchPhrase TEXT NOT NULL,
+    AdvEngineID SMALLINT NOT NULL,
+    IsArtifical SMALLINT NOT NULL,
+    WindowClientWidth SMALLINT NOT NULL,
+    WindowClientHeight SMALLINT NOT NULL,
+    ClientTimeZone SMALLINT NOT NULL,
+    ClientEventTime TIMESTAMP NOT NULL,
+    SilverlightVersion1 SMALLINT NOT NULL,
+    SilverlightVersion2 SMALLINT NOT NULL,
+    SilverlightVersion3 INTEGER NOT NULL,
+    SilverlightVersion4 SMALLINT NOT NULL,
+    PageCharset TEXT NOT NULL,
+    CodeVersion INTEGER NOT NULL,
+    IsLink SMALLINT NOT NULL,
+    IsDownload SMALLINT NOT NULL,
+    IsNotBounce SMALLINT NOT NULL,
+    FUniqID BIGINT NOT NULL,
+    OriginalURL TEXT NOT NULL,
+    HID INTEGER NOT NULL,
+    IsOldCounter SMALLINT NOT NULL,
+    IsEvent SMALLINT NOT NULL,
+    IsParameter SMALLINT NOT NULL,
+    DontCountHits SMALLINT NOT NULL,
+    WithHash SMALLINT NOT NULL,
+    HitColor CHAR NOT NULL,
+    LocalEventTime TIMESTAMP NOT NULL,
+    Age SMALLINT NOT NULL,
+    Sex SMALLINT NOT NULL,
+    Income SMALLINT NOT NULL,
+    Interests SMALLINT NOT NULL,
+    Robotness SMALLINT NOT NULL,
+    RemoteIP INTEGER NOT NULL,
+    WindowName INTEGER NOT NULL,
+    OpenerName INTEGER NOT NULL,
+    HistoryLength SMALLINT NOT NULL,
+    BrowserLanguage TEXT NOT NULL,
+    BrowserCountry TEXT NOT NULL,
+    SocialNetwork TEXT NOT NULL,
+    SocialAction TEXT NOT NULL,
+    HTTPError SMALLINT NOT NULL,
+    SendTiming INTEGER NOT NULL,
+    DNSTiming INTEGER NOT NULL,
+    ConnectTiming INTEGER NOT NULL,
+    ResponseStartTiming INTEGER NOT NULL,
+    ResponseEndTiming INTEGER NOT NULL,
+    FetchTiming INTEGER NOT NULL,
+    SocialSourceNetworkID SMALLINT NOT NULL,
+    SocialSourcePage TEXT NOT NULL,
+    ParamPrice BIGINT NOT NULL,
+    ParamOrderID TEXT NOT NULL,
+    ParamCurrency TEXT NOT NULL,
+    ParamCurrencyID SMALLINT NOT NULL,
+    OpenstatServiceName TEXT NOT NULL,
+    OpenstatCampaignID TEXT NOT NULL,
+    OpenstatAdID TEXT NOT NULL,
+    OpenstatSourceID TEXT NOT NULL,
+    UTMSource TEXT NOT NULL,
+    UTMMedium TEXT NOT NULL,
+    UTMCampaign TEXT NOT NULL,
+    UTMContent TEXT NOT NULL,
+    UTMTerm TEXT NOT NULL,
+    FromTag TEXT NOT NULL,
+    HasGCLID SMALLINT NOT NULL,
+    RefererHash BIGINT NOT NULL,
+    URLHash BIGINT NOT NULL,
+    CLID INTEGER NOT NULL,
+    PRIMARY KEY (CounterID, EventDate, UserID, EventTime, WatchID)
+) ENGINE=DuckDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;

mariadb-duckdb/data-size

@@ -0,0 +1,14 @@
+#!/bin/bash
+set -eu
+
+# DuckDB engine stores all data in a single duckdb.db file in the MariaDB data
+# directory. information_schema.TABLES does not report DuckDB storage size, so
+# we measure the file directly.
+DUCKDB_FILE="/var/lib/mysql/duckdb.db"
+
+if [ ! -f "$DUCKDB_FILE" ]; then
+    echo "0"
+    exit 0
+fi
+
+du -sb "$DUCKDB_FILE" | awk '{print $1}'

mariadb-duckdb/install

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+#!/bin/bash
+set -eu
+
+CI_SOURCES_URL="https://ci.mariadb.org/68929/amd64-ubuntu-2404-deb-autobake/mariadb.sources"
+
+# Idempotent: if DuckDB plugin is already active, nothing to do.
+if sudo mariadb -e "SELECT PLUGIN_STATUS FROM information_schema.PLUGINS WHERE PLUGIN_NAME='DuckDB';" 2>/dev/null | grep -q 'ACTIVE'; then
+    echo "MariaDB with DuckDB engine already installed and active."
+    exit 0
+fi
+
+# Remove any conflicting MariaDB/MySQL installation to avoid package conflicts.
+# On a fresh EC2 instance Ubuntu 24.04 may ship with mariadb stubs.
+if dpkg -l | grep -qE '^ii\s+(mariadb-server|mysql-server)'; then
+    echo "Removing existing MariaDB/MySQL installation..."
+    sudo systemctl stop mariadb mysql 2>/dev/null || true
+    sudo apt-get purge -y 'mariadb-server*' 'mariadb-client*' 'mariadb-common*' \
+        'mysql-server*' 'mysql-client*' 'libmariadb*' 'libmysqlclient*' 2>/dev/null || true
+    sudo rm -rf /var/lib/mysql /etc/mysql
+fi
+
+# Add MariaDB CI build as apt source (Trusted: yes — unsigned CI packages, testing only).
+sudo wget -q -O /etc/apt/sources.list.d/mariadb-duckdb-ci.sources "$CI_SOURCES_URL"
+
+sudo apt-get update -y
+sudo DEBIAN_FRONTEND=noninteractive apt-get install -y \
+    mariadb-server mariadb-client
+
+# Configure the DuckDB storage engine plugin (from mariadb.org article defaults).
+sudo tee /etc/mysql/mariadb.conf.d/duckdb.cnf >/dev/null <<'EOF'
+[mysqld]
+plugin-maturity=alpha
+plugin-load-add=ha_duckdb.so
+duckdb-memory-limit=24G
+EOF
+
+sudo systemctl enable mariadb
+sudo systemctl restart mariadb
+
+# Smoke-test: DuckDB plugin must be ACTIVE.
+sudo mariadb -e "SELECT PLUGIN_STATUS FROM information_schema.PLUGINS WHERE PLUGIN_NAME='DuckDB';" \
+    | grep -q 'ACTIVE' || { echo "ERROR: DuckDB plugin not active after restart" >&2; exit 1; }
+
+# Allow the mysql user (which runs DuckDB embedded) to traverse the home
+# directory so COPY FROM can read dataset files anywhere under ~.
+sudo chmod o+x /home/ubuntu
+
+echo "MariaDB with DuckDB engine installed and ready."

mariadb-duckdb/load

@@ -0,0 +1,34 @@
+#!/bin/bash
+set -eu
+
+# Helper: run a DuckDB SQL statement through MariaDB's run_in_duckdb UDF.
+# Single quotes inside $1 are doubled so they survive the MariaDB string literal.
+duck() {
+    local esc
+    esc=$(printf '%s' "$1" | sed "s/'/''/g")
+    sudo mariadb -N -e "SELECT run_in_duckdb('$esc')"
+}
+
+sudo mariadb -e "DROP DATABASE IF EXISTS test"
+sudo mariadb -e "CREATE DATABASE test"
+sudo mariadb test < create.sql
+
+# Load via DuckDB's native vectorized CSV reader (12x faster than LOAD DATA LOCAL
+# INFILE which routes every row through MariaDB's single-threaded write_row path).
+# hits.tsv is tab-delimited with datetime strings in TIMESTAMP columns, matching
+# the table schema — no type conversion needed.
+#
+# DuckDB glob expander requires read permission on all parent directories.
+# /home/ubuntu is mode 751 (o+x only) so DuckDB can traverse but not list it,
+# causing "No files found" errors. Hardlink to /var/lib/mysql/ (mysql-owned,
+# mode 755) resolves this instantly without copying 70 GB.
+HITS_LINK=/var/lib/mysql/hits_load.tsv
+sudo ln "$(realpath hits.tsv)" "$HITS_LINK"
+sudo chmod 644 "$HITS_LINK"
+# NULLSTR '\N' matches MySQL/MariaDB convention: only \N is NULL, empty fields → ''.
+# Without this, DuckDB treats every empty TSV field as NULL → NOT NULL violations.
+duck "COPY test.hits FROM '$HITS_LINK' (FORMAT CSV, DELIMITER '\t', NULLSTR '\N')"
+
+sudo rm -f "$HITS_LINK"
+rm -f hits.tsv
+sync

mariadb-duckdb/queries.sql

@@ -0,0 +1,43 @@
+SELECT COUNT(*) FROM hits;
+SELECT COUNT(*) FROM hits WHERE AdvEngineID <> 0;
+SELECT SUM(AdvEngineID), COUNT(*), AVG(ResolutionWidth) FROM hits;
+SELECT AVG(UserID) FROM hits;
+SELECT COUNT(DISTINCT UserID) FROM hits;
+SELECT COUNT(DISTINCT SearchPhrase) FROM hits;
+SELECT MIN(EventDate), MAX(EventDate) FROM hits;
+SELECT AdvEngineID, COUNT(*) FROM hits WHERE AdvEngineID <> 0 GROUP BY AdvEngineID ORDER BY COUNT(*) DESC;
+SELECT RegionID, COUNT(DISTINCT UserID) AS u FROM hits GROUP BY RegionID ORDER BY u DESC LIMIT 10;
+SELECT RegionID, SUM(AdvEngineID), COUNT(*) AS c, AVG(ResolutionWidth), COUNT(DISTINCT UserID) FROM hits GROUP BY RegionID ORDER BY c DESC LIMIT 10;
+SELECT MobilePhoneModel, COUNT(DISTINCT UserID) AS u FROM hits WHERE MobilePhoneModel <> '' GROUP BY MobilePhoneModel ORDER BY u DESC LIMIT 10;
+SELECT MobilePhone, MobilePhoneModel, COUNT(DISTINCT UserID) AS u FROM hits WHERE MobilePhoneModel <> '' GROUP BY MobilePhone, MobilePhoneModel ORDER BY u DESC LIMIT 10;
+SELECT SearchPhrase, COUNT(*) AS c FROM hits WHERE SearchPhrase <> '' GROUP BY SearchPhrase ORDER BY c DESC LIMIT 10;
+SELECT SearchPhrase, COUNT(DISTINCT UserID) AS u FROM hits WHERE SearchPhrase <> '' GROUP BY SearchPhrase ORDER BY u DESC LIMIT 10;
+SELECT SearchEngineID, SearchPhrase, COUNT(*) AS c FROM hits WHERE SearchPhrase <> '' GROUP BY SearchEngineID, SearchPhrase ORDER BY c DESC LIMIT 10;
+SELECT UserID, COUNT(*) FROM hits GROUP BY UserID ORDER BY COUNT(*) DESC LIMIT 10;
+SELECT UserID, SearchPhrase, COUNT(*) FROM hits GROUP BY UserID, SearchPhrase ORDER BY COUNT(*) DESC LIMIT 10;
+SELECT UserID, SearchPhrase, COUNT(*) FROM hits GROUP BY UserID, SearchPhrase LIMIT 10;
+SELECT UserID, extract(minute FROM EventTime) AS m, SearchPhrase, COUNT(*) FROM hits GROUP BY UserID, m, SearchPhrase ORDER BY COUNT(*) DESC LIMIT 10;
+SELECT UserID FROM hits WHERE UserID = 435090932899640449;
+SELECT COUNT(*) FROM hits WHERE URL LIKE '%google%';
+SELECT SearchPhrase, MIN(URL), COUNT(*) AS c FROM hits WHERE URL LIKE '%google%' AND SearchPhrase <> '' GROUP BY SearchPhrase ORDER BY c DESC LIMIT 10;
+SELECT SearchPhrase, MIN(URL), MIN(Title), COUNT(*) AS c, COUNT(DISTINCT UserID) FROM hits WHERE Title LIKE '%Google%' AND URL NOT LIKE '%.google.%' AND SearchPhrase <> '' GROUP BY SearchPhrase ORDER BY c DESC LIMIT 10;
+SELECT * FROM hits WHERE URL LIKE '%google%' ORDER BY EventTime LIMIT 10;
+SELECT SearchPhrase FROM hits WHERE SearchPhrase <> '' ORDER BY EventTime LIMIT 10;
+SELECT SearchPhrase FROM hits WHERE SearchPhrase <> '' ORDER BY SearchPhrase LIMIT 10;
+SELECT SearchPhrase FROM hits WHERE SearchPhrase <> '' ORDER BY EventTime, SearchPhrase LIMIT 10;
+SELECT CounterID, AVG(length(URL)) AS l, COUNT(*) AS c FROM hits WHERE URL <> '' GROUP BY CounterID HAVING COUNT(*) > 100000 ORDER BY l DESC LIMIT 25;
+SELECT REGEXP_REPLACE(Referer, '^https?://(?:www\.)?([^/]+)/.*$', '\1') AS k, AVG(length(Referer)) AS l, COUNT(*) AS c, MIN(Referer) FROM hits WHERE Referer <> '' GROUP BY k HAVING COUNT(*) > 100000 ORDER BY l DESC LIMIT 25;
+SELECT SUM(ResolutionWidth), SUM(ResolutionWidth + 1), SUM(ResolutionWidth + 2), SUM(ResolutionWidth + 3), SUM(ResolutionWidth + 4), SUM(ResolutionWidth + 5), SUM(ResolutionWidth + 6), SUM(ResolutionWidth + 7), SUM(ResolutionWidth + 8), SUM(ResolutionWidth + 9), SUM(ResolutionWidth + 10), SUM(ResolutionWidth + 11), SUM(ResolutionWidth + 12), SUM(ResolutionWidth + 13), SUM(ResolutionWidth + 14), SUM(ResolutionWidth + 15), SUM(ResolutionWidth + 16), SUM(ResolutionWidth + 17), SUM(ResolutionWidth + 18), SUM(ResolutionWidth + 19), SUM(ResolutionWidth + 20), SUM(ResolutionWidth + 21), SUM(ResolutionWidth + 22), SUM(ResolutionWidth + 23), SUM(ResolutionWidth + 24), SUM(ResolutionWidth + 25), SUM(ResolutionWidth + 26), SUM(ResolutionWidth + 27), SUM(ResolutionWidth + 28), SUM(ResolutionWidth + 29), SUM(ResolutionWidth + 30), SUM(ResolutionWidth + 31), SUM(ResolutionWidth + 32), SUM(ResolutionWidth + 33), SUM(ResolutionWidth + 34), SUM(ResolutionWidth + 35), SUM(ResolutionWidth + 36), SUM(ResolutionWidth + 37), SUM(ResolutionWidth + 38), SUM(ResolutionWidth + 39), SUM(ResolutionWidth + 40), SUM(ResolutionWidth + 41), SUM(ResolutionWidth + 42), SUM(ResolutionWidth + 43), SUM(ResolutionWidth + 44), SUM(ResolutionWidth + 45), SUM(ResolutionWidth + 46), SUM(ResolutionWidth + 47), SUM(ResolutionWidth + 48), SUM(ResolutionWidth + 49), SUM(ResolutionWidth + 50), SUM(ResolutionWidth + 51), SUM(ResolutionWidth + 52), SUM(ResolutionWidth + 53), SUM(ResolutionWidth + 54), SUM(ResolutionWidth + 55), SUM(ResolutionWidth + 56), SUM(ResolutionWidth + 57), SUM(ResolutionWidth + 58), SUM(ResolutionWidth + 59), SUM(ResolutionWidth + 60), SUM(ResolutionWidth + 61), SUM(ResolutionWidth + 62), SUM(ResolutionWidth + 63), SUM(ResolutionWidth + 64), SUM(ResolutionWidth + 65), SUM(ResolutionWidth + 66), SUM(ResolutionWidth + 67), SUM(ResolutionWidth + 68), SUM(ResolutionWidth + 69), SUM(ResolutionWidth + 70), SUM(ResolutionWidth + 71), SUM(ResolutionWidth + 72), SUM(ResolutionWidth + 73), SUM(ResolutionWidth + 74), SUM(ResolutionWidth + 75), SUM(ResolutionWidth + 76), SUM(ResolutionWidth + 77), SUM(ResolutionWidth + 78), SUM(ResolutionWidth + 79), SUM(ResolutionWidth + 80), SUM(ResolutionWidth + 81), SUM(ResolutionWidth + 82), SUM(ResolutionWidth + 83), SUM(ResolutionWidth + 84), SUM(ResolutionWidth + 85), SUM(ResolutionWidth + 86), SUM(ResolutionWidth + 87), SUM(ResolutionWidth + 88), SUM(ResolutionWidth + 89) FROM hits;
+SELECT SearchEngineID, ClientIP, COUNT(*) AS c, SUM(IsRefresh), AVG(ResolutionWidth) FROM hits WHERE SearchPhrase <> '' GROUP BY SearchEngineID, ClientIP ORDER BY c DESC LIMIT 10;
+SELECT WatchID, ClientIP, COUNT(*) AS c, SUM(IsRefresh), AVG(ResolutionWidth) FROM hits WHERE SearchPhrase <> '' GROUP BY WatchID, ClientIP ORDER BY c DESC LIMIT 10;
+SELECT WatchID, ClientIP, COUNT(*) AS c, SUM(IsRefresh), AVG(ResolutionWidth) FROM hits GROUP BY WatchID, ClientIP ORDER BY c DESC LIMIT 10;
+SELECT URL, COUNT(*) AS c FROM hits GROUP BY URL ORDER BY c DESC LIMIT 10;
+SELECT 1, URL, COUNT(*) AS c FROM hits GROUP BY 1, URL ORDER BY c DESC LIMIT 10;
+SELECT ClientIP, ClientIP - 1, ClientIP - 2, ClientIP - 3, COUNT(*) AS c FROM hits GROUP BY ClientIP, ClientIP - 1, ClientIP - 2, ClientIP - 3 ORDER BY c DESC LIMIT 10;
+SELECT URL, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-01' AND EventDate <= '2013-07-31' AND DontCountHits = 0 AND IsRefresh = 0 AND URL <> '' GROUP BY URL ORDER BY PageViews DESC LIMIT 10;
+SELECT Title, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-01' AND EventDate <= '2013-07-31' AND DontCountHits = 0 AND IsRefresh = 0 AND Title <> '' GROUP BY Title ORDER BY PageViews DESC LIMIT 10;
+SELECT URL, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-01' AND EventDate <= '2013-07-31' AND IsRefresh = 0 AND IsLink <> 0 AND IsDownload = 0 GROUP BY URL ORDER BY PageViews DESC LIMIT 10 OFFSET 1000;
+SELECT TraficSourceID, SearchEngineID, AdvEngineID, CASE WHEN (SearchEngineID = 0 AND AdvEngineID = 0) THEN Referer ELSE '' END AS Src, URL AS Dst, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-01' AND EventDate <= '2013-07-31' AND IsRefresh = 0 GROUP BY TraficSourceID, SearchEngineID, AdvEngineID, Src, Dst ORDER BY PageViews DESC LIMIT 10 OFFSET 1000;
+SELECT URLHash, EventDate, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-01' AND EventDate <= '2013-07-31' AND IsRefresh = 0 AND TraficSourceID IN (-1, 6) AND RefererHash = 3594120000172545465 GROUP BY URLHash, EventDate ORDER BY PageViews DESC LIMIT 10 OFFSET 100;
+SELECT WindowClientWidth, WindowClientHeight, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-01' AND EventDate <= '2013-07-31' AND IsRefresh = 0 AND DontCountHits = 0 AND URLHash = 2868770270353813622 GROUP BY WindowClientWidth, WindowClientHeight ORDER BY PageViews DESC LIMIT 10 OFFSET 10000;
+SELECT CONCAT(YEAR(EventTime),'-',LPAD(CAST(MONTH(EventTime) AS CHAR),2,'0'),'-',LPAD(CAST(DAY(EventTime) AS CHAR),2,'0'),' ',LPAD(CAST(HOUR(EventTime) AS CHAR),2,'0'),':',LPAD(CAST(MINUTE(EventTime) AS CHAR),2,'0'),':00') AS M, COUNT(*) AS PageViews FROM hits WHERE CounterID = 62 AND EventDate >= '2013-07-14' AND EventDate <= '2013-07-15' AND IsRefresh = 0 AND DontCountHits = 0 GROUP BY M ORDER BY M LIMIT 10 OFFSET 1000;

mariadb-duckdb/query

@@ -0,0 +1,38 @@
+#!/bin/bash
+# Reads a SQL query from stdin, runs it via `mariadb -vvv` against the `test` DB.
+# Stdout: query result.
+# Stderr: query runtime in fractional seconds on the last line (parsed from
+# mariadb's "N rows in set (X.XX sec)" footer; days/hours/min/sec all handled).
+# Exit non-zero on error.
+set -e
+
+query=$(cat)
+
+out=$(sudo mariadb test -vvv -e "$query" 2>&1) && exit_code=0 || exit_code=$?
+
+if [ "$exit_code" -ne 0 ] || printf '%s\n' "$out" | grep -q '^ERROR'; then
+    printf '%s\n' "$out" >&2
+    exit 1
+fi
+
+printf '%s\n' "$out"
+
+# mariadb may print "(2 days 3 hours 4 min 5.6 sec)" or any subset.
+parsed=$(printf '%s\n' "$out" \
+    | grep -P 'rows? in set|Empty set|Query OK' \
+    | tail -n1 \
+    | sed -r 's/^.*?\((([0-9.]+) days? )?(([0-9.]+) hours? )?(([0-9.]+) min )?([0-9.]+) sec\).*?$/\2,\4,\6,\7/')
+
+if [ -z "$parsed" ]; then
+    echo "no timing in mariadb output" >&2
+    exit 1
+fi
+
+awk -F, -v p="$parsed" 'BEGIN {
+    n = split(p, a, ",")
+    d = (a[1] == "") ? 0 : a[1]
+    h = (a[2] == "") ? 0 : a[2]
+    m = (a[3] == "") ? 0 : a[3]
+    s = (a[4] == "") ? 0 : a[4]
+    printf "%.3f\n", d * 86400 + h * 3600 + m * 60 + s
+}' >&2