From 81cd0b0b8f5144083f8491d2413fa5c8e0382b67 Mon Sep 17 00:00:00 2001
From: James Cor <jcor@ucsd.edu>
Date: Mon, 15 Apr 2024 16:46:54 -0700
Subject: [PATCH] add table comments to `information_schema.tables` (#2458)

---
 enginetest/queries/information_schema_queries.go | 15 +++++++++++++++
 sql/information_schema/information_schema.go     |  7 ++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/enginetest/queries/information_schema_queries.go b/enginetest/queries/information_schema_queries.go
index 1581452a67..5df834cd35 100644
--- a/enginetest/queries/information_schema_queries.go
+++ b/enginetest/queries/information_schema_queries.go
@@ -1717,6 +1717,21 @@ from information_schema.routines where routine_schema = 'mydb' and routine_type
 			},
 		},
 	},
+	{
+
+		Name: "information_schema.tables has table comments",
+		SetUpScript: []string{
+			"create table t (i int primary key) comment 'this is a table comment';",
+		},
+		Assertions: []ScriptTestAssertion{
+			{
+				Query: "select table_comment from information_schema.tables where table_name = 't';",
+				Expected: []sql.Row{
+					{"this is a table comment"},
+				},
+			},
+		},
+	},
 }
 
 var SkippedInfoSchemaScripts = []ScriptTest{
diff --git a/sql/information_schema/information_schema.go b/sql/information_schema/information_schema.go
index b234dac661..64c8392456 100644
--- a/sql/information_schema/information_schema.go
+++ b/sql/information_schema/information_schema.go
@@ -1822,6 +1822,7 @@ func tablesRowIter(ctx *Context, cat Catalog) (RowIter, error) {
 		y2k, _, _ := types.Timestamp.Convert("2000-01-01 00:00:00")
 		err := DBTableIter(ctx, db, func(t Table) (cont bool, err error) {
 			tableCollation = t.Collation().String()
+			comment := ""
 			if db.Name() != InformationSchemaDatabaseName {
 				if st, ok := t.(StatisticsTable); ok {
 					tableRows, _, err = st.RowCount(ctx)
@@ -1856,6 +1857,10 @@ func tablesRowIter(ctx *Context, cat Catalog) (RowIter, error) {
 						autoInc = nil
 					}
 				}
+
+				if commentedTable, ok := t.(CommentedTable); ok {
+					comment = commentedTable.Comment()
+				}
 			}
 
 			rows = append(rows, Row{
@@ -1879,7 +1884,7 @@ func tablesRowIter(ctx *Context, cat Catalog) (RowIter, error) {
 				tableCollation, // table_collation
 				nil,            // checksum
 				"",             // create_options
-				"",             // table_comment
+				comment,        // table_comment
 			})
 
 			return true, nil