add test

regression-test/data/variant_p0/desc.out

@@ -198,3 +198,11 @@ v.金额	SMALLINT	Yes	false	\N	NONE
 k	BIGINT	Yes	true	\N	
 v	VARIANT	Yes	false	\N	NONE
 
+-- !sql15 --
+k	BIGINT	Yes	true	\N	
+v	VARIANT	Yes	false	\N	NONE
+v.a	TINYINT	Yes	false	\N	NONE
+v.b	TINYINT	Yes	false	\N	NONE
+v.c	TINYINT	Yes	false	\N	NONE
+v.d	TINYINT	Yes	false	\N	NONE
+

regression-test/suites/variant_p0/desc.groovy

@@ -238,6 +238,23 @@ suite("regression_test_variant_desc", "nonConcurrent"){
         sql """ insert into ${table_name} values (0, '100')"""
         sql """set describe_extend_variant_column = true"""
         qt_sql_12 """desc ${table_name}"""
+
+
+        // desc with large tablets
+        table_name = "large_tablets"
+        create_table_partition.call(table_name, "200") 
+        sql """insert into large_tablets values (1, '{"a" : 10}')"""
+        sql """insert into large_tablets values (3001, '{"b" : 10}')"""
+        sql """insert into large_tablets values (50001, '{"c" : 10}')"""
+        sql """insert into large_tablets values (99999, '{"d" : 10}')"""
+        sql """set max_fetch_remote_schema_tablet_count = 2"""
+        sql "desc large_tablets"
+        sql """set max_fetch_remote_schema_tablet_count = 128"""
+        sql "desc large_tablets"
+        sql """set max_fetch_remote_schema_tablet_count = 512"""
+        sql "desc large_tablets"
+        sql """set max_fetch_remote_schema_tablet_count = 2048"""
+        qt_sql15 "desc large_tablets"
     } finally {
         // reset flags
         set_be_config.call("variant_ratio_of_defaults_as_sparse_column", "0.95")