Merge pull request #5437 from TCeason/bug_fix

ISSUES-5432 fix bad alloc when truncate join storage

dbms/src/Storages/StorageJoin.h

@@ -43,7 +43,7 @@ public:
 
 private:
     Block sample_block;
-    const Names & key_names;
+    const Names key_names;
     bool use_nulls;
     SizeLimits limits;
     ASTTableJoin::Kind kind;                    /// LEFT | INNER ...

dbms/tests/queries/0_stateless/00950_bad_alloc_when_truncate_join_storage.sql

+DROP TABLE IF EXISTS test.join_test;
+CREATE TABLE test.join_test (number UInt8, value Float32) Engine = Join(ANY, LEFT, number);
+TRUNCATE TABLE test.join_test;
+DROP TABLE IF EXISTS test.join_test;