diff --git a/pglablib/sqlparser/Parser.cpp b/pglablib/sqlparser/Parser.cpp
index c8a192b..92e6019 100644
--- a/pglablib/sqlparser/Parser.cpp
+++ b/pglablib/sqlparser/Parser.cpp
@@ -3,7 +3,11 @@
 
 
 Parser::Parser(const std::string &input_string)
-    : InputStream(std::make_unique<antlr4::ANTLRInputStream>(input_string))
+    : Parser(std::make_unique<antlr4::ANTLRInputStream>(input_string))
+{}
+
+Parser::Parser(std::unique_ptr<antlr4::CharStream> stream)
+    : InputStream(std::move(stream))
     , CaseFilter(InputStream.get(), true)
     , Lexer(&CaseFilter)
     , TokenStream(&Lexer)
diff --git a/pglablib/sqlparser/Parser.h b/pglablib/sqlparser/Parser.h
index 01b905b..7633252 100644
--- a/pglablib/sqlparser/Parser.h
+++ b/pglablib/sqlparser/Parser.h
@@ -9,6 +9,7 @@ class Parser
 {
 public:
     Parser(const std::string &input_string);
+    Parser(std::unique_ptr<antlr4::CharStream> stream);
 
     std::unique_ptr<sqlast::StatementList> Parse();