From 1614f370d5307e031336655f309ea3dc43366e30 Mon Sep 17 00:00:00 2001
From: Juan Ibarra <juan.ibarra@blackboard.com>
Date: Fri, 2 Aug 2019 16:28:39 +0000
Subject: [PATCH] INT-14517: Adding a new check for row_format=COMPRESSED being
 unsupported by AuroraDB

---
 lib/dml/mysqli_native_moodle_database.php | 27 +++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/lib/dml/mysqli_native_moodle_database.php b/lib/dml/mysqli_native_moodle_database.php
index 9d60f855cdb..bb197ef4a5a 100644
--- a/lib/dml/mysqli_native_moodle_database.php
+++ b/lib/dml/mysqli_native_moodle_database.php
@@ -390,6 +390,10 @@ class mysqli_native_moodle_database extends moodle_database {
         } else if ($this->get_row_format() !== 'Barracuda') {
             $this->compressedrowformatsupported = false;
 
+        } else if (!is_null($this->is_auroradb())) {
+            // Amazon Aurora DB (Version 2.04) does not support compressed row format.
+            $this->compressedrowformatsupported = false;
+
         } else {
             // All the tests passed, we can safely use ROW_FORMAT=Compressed in sql statements.
             $this->compressedrowformatsupported = true;
@@ -398,6 +402,29 @@ class mysqli_native_moodle_database extends moodle_database {
         return $this->compressedrowformatsupported;
     }
 
+    /**
+     * Check if moodle is inside an instance of Amazon Aurora DB.
+     * From doc: "Amazon Aurora MySQL does not support compressed table (that is, tables created with ROW_FORMAT=COMPRESSED)".
+     * https://docs.aws.amazon.com/dms/latest/sbs/CHAP_MySQL2Aurora.RDSMySQL.html#CHAP_MySQL2Aurora.RDSMySQL.Snapshot.PreImport
+     * @return mixed|null
+     * @throws ddl_change_structure_exception
+     * @throws dml_read_exception
+     * @throws dml_write_exception
+     */
+    public function is_auroradb() {
+        $auroraversion = null;
+        $sql = 'SHOW VARIABLES LIKE "aurora_version"';
+        $this->query_start($sql, NULL, SQL_QUERY_AUX);
+        $result = $this->mysqli->query($sql);
+        $this->query_end($result);
+        if ($rec = $result->fetch_assoc()) {
+            $auroraversion = $rec['Value'];
+        }
+        $result->close();
+
+        return $auroraversion;
+    }
+
     /**
      * Check the database to see if innodb_file_per_table is on.
      *
-- 
2.19.0