Added a test from Boris Granveaud ClickHouse#3421

dbms/tests/queries/bugs/00816_concurrent_alter_column.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+set -e
+
+CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+. $CURDIR/../shell_config.sh
+
+echo "DROP TABLE IF EXISTS test.test" | ${CLICKHOUSE_CLIENT}
+echo "CREATE TABLE test.test (ts DATETIME) ENGINE = MergeTree PARTITION BY toStartOfDay(ts) ORDER BY tuple()" | ${CLICKHOUSE_CLIENT}
+
+for i in {1..500}; do echo "ALTER TABLE test.test ADD COLUMN c$i DOUBLE;"; done | ${CLICKHOUSE_CLIENT} -n
+
+for i in {1..500}; do echo "ALTER TABLE test.test ADD COLUMN d DOUBLE" | ${CLICKHOUSE_CLIENT}; echo "ALTER TABLE test.test DROP COLUMN d" | ${CLICKHOUSE_CLIENT} -n; done &
+for i in {1..500}; do echo "ALTER TABLE test.test ADD COLUMN e DOUBLE" | ${CLICKHOUSE_CLIENT}; echo "ALTER TABLE test.test DROP COLUMN e" | ${CLICKHOUSE_CLIENT} -n; done &
+
+wait
+
+echo "DROP TABLE test.test" | ${CLICKHOUSE_CLIENT}