From 2e9900ea24a15807e74ca606db972e04235ac368 Mon Sep 17 00:00:00 2001
From: Leonid Fedorov <leonid.fedorov@mariadb.com>
Date: Mon, 1 Sep 2025 14:22:48 +0000
Subject: [PATCH] test(rbo): initial test

---
 .../columnstore/future/rbo_parallel_ces.test  | 71 +++++++++++++++++++
 .../columnstore/include/cross_engine.inc      | 17 +++++
 2 files changed, 88 insertions(+)
 create mode 100644 mysql-test/columnstore/future/rbo_parallel_ces.test
 create mode 100644 mysql-test/columnstore/include/cross_engine.inc

diff --git a/mysql-test/columnstore/future/rbo_parallel_ces.test b/mysql-test/columnstore/future/rbo_parallel_ces.test
new file mode 100644
index 000000000..80cada4a1
--- /dev/null
+++ b/mysql-test/columnstore/future/rbo_parallel_ces.test
@@ -0,0 +1,71 @@
+--source ../include/have_columnstore.inc
+--source ../include/functions.inc
+--source ../include/cross_engine.inc
+
+
+--disable_warnings
+DROP DATABASE IF EXISTS rbo_parallel_ces;
+--enable_warnings
+
+CREATE DATABASE rbo_parallel_ces;
+USE rbo_parallel_ces;
+
+# Turn on plan logging to capture CSEP strings
+SELECT calsettrace(1);
+
+# Test table in InnoDB (routed to ColumnStore via CES)
+CREATE TABLE Ti (col1 INT, col2 INT, col3 INT) ENGINE=InnoDB;
+
+# Populate with 100 rows
+INSERT INTO Ti (col1, col2, col3)
+SELECT seq, seq+1, seq+2 FROM (SELECT seq FROM seq_1_to_100) AS numbers;
+
+# Generate statistics, limit histogram size
+SET @@histogram_size=10;
+ANALYZE TABLE Ti PERSISTENT FOR ALL;
+
+# Index to make basic stats available
+CREATE INDEX excellent_index ON Ti(col1);
+
+# Enable RBO
+SET @@columnstore_unstable_optimizer=ON;
+SET @@optimizer_switch='derived_merge=off';
+
+# First run with parallel factor 5
+SET @@columnstore_ces_optimization_parallel_factor=5;
+
+# Execute a query to build and store plans
+SELECT SUM(col1) FROM Ti;
+
+# Snapshot plans into variables for readability
+SET @orig_plan := mcsgetplan('original');
+SET @opt_plan := mcsgetplan('optimized');
+SET @rbo_rules := mcsgetplan('rules');
+
+# Validate plan contents using stored plans
+# Count Union Units by looking for opening unit blocks after the marker '--- Union Unit ---'
+SET @uu_tail := SUBSTRING_INDEX(@orig_plan, '--- Union Unit ---', -1);
+SET @unit_open := CONCAT(CHAR(10),'    {',CHAR(10));
+SELECT (CHAR_LENGTH(@uu_tail) - CHAR_LENGTH(REPLACE(@uu_tail, @unit_open, '')))/CHAR_LENGTH(@unit_open) AS unions_original;
+
+SET @uu_tail := SUBSTRING_INDEX(@opt_plan, '--- Union Unit ---', -1);
+SELECT (CHAR_LENGTH(@uu_tail) - CHAR_LENGTH(REPLACE(@uu_tail, @unit_open, '')))/CHAR_LENGTH(@unit_open) AS unions_optimized_5;
+
+# Ensure rule was applied
+SELECT @rbo_rules LIKE '%parallel_ces%' AS rule_parallel_ces_applied;
+
+# Increase factor to 15 but expect 10 unions due to histogram_size cap
+SET @@columnstore_ces_optimization_parallel_factor=15;
+
+# Re-execute to rebuild plan with new factor
+SELECT SUM(col1) FROM Ti;
+
+SET @opt_plan := mcsgetplan('optimized');
+SET @uu_tail := SUBSTRING_INDEX(@opt_plan, '--- Union Unit ---', -1);
+SELECT (CHAR_LENGTH(@uu_tail) - CHAR_LENGTH(REPLACE(@uu_tail, @unit_open, '')))/CHAR_LENGTH(@unit_open) AS unions_optimized_15;
+
+# Cleanup
+SELECT calsettrace(0);
+DROP DATABASE rbo_parallel_ces;
+
+--source ../include/drop_functions.inc
diff --git a/mysql-test/columnstore/include/cross_engine.inc b/mysql-test/columnstore/include/cross_engine.inc
new file mode 100644
index 000000000..5eca6141a
--- /dev/null
+++ b/mysql-test/columnstore/include/cross_engine.inc
@@ -0,0 +1,17 @@
+# -------------------------------------------------------------- #
+# Enable cross engine join
+# Configure user and password in Columnstore.xml file
+# -------------------------------------------------------------- #
+--exec /usr/bin/mcsSetConfig CrossEngineSupport User 'cejuser'
+--exec /usr/bin/mcsSetConfig CrossEngineSupport Password 'Vagrant1|0000001'
+# -------------------------------------------------------------- #
+# Create corresponding in the server
+# -------------------------------------------------------------- #
+
+--disable_warnings
+CREATE USER IF NOT EXISTS'cejuser'@'localhost' IDENTIFIED BY 'Vagrant1|0000001';
+--enable_warnings
+
+GRANT ALL PRIVILEGES ON *.* TO 'cejuser'@'localhost';
+FLUSH PRIVILEGES;
+