From 15a950245cda4a22db60db9f2193ee84b7b4f89b Mon Sep 17 00:00:00 2001
From: Mark Raasveldt <mark.raasveldt@gmail.com>
Date: Wed, 3 Jul 2024 15:05:47 +0200
Subject: [PATCH] Add support for reducing PreparedStatement

---
 src/include/statement_simplifier.hpp |  2 ++
 src/statement_simplifier.cpp         |  8 ++++++++
 test/sql/sql_reduce.test             | 15 ++++++++++++++-
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/include/statement_simplifier.hpp b/src/include/statement_simplifier.hpp
index 0f23843..f27b0d6 100644
--- a/src/include/statement_simplifier.hpp
+++ b/src/include/statement_simplifier.hpp
@@ -16,6 +16,7 @@ class SQLStatement;
 class SelectStatement;
 class InsertStatement;
 class UpdateStatement;
+class PrepareStatement;
 class DeleteStatement;
 class TableRef;
 class SelectNode;
@@ -41,6 +42,7 @@ class StatementSimplifier {
 	void Simplify(SelectStatement &stmt);
 	void Simplify(InsertStatement &stmt);
 	void Simplify(UpdateStatement &stmt);
+	void Simplify(PrepareStatement &stmt);
 	void Simplify(DeleteStatement &stmt);
 
 	void Simplification();
diff --git a/src/statement_simplifier.cpp b/src/statement_simplifier.cpp
index 66662f4..60f466f 100644
--- a/src/statement_simplifier.cpp
+++ b/src/statement_simplifier.cpp
@@ -8,6 +8,7 @@
 #include "duckdb/parser/expression/list.hpp"
 #include "duckdb/parser/statement/delete_statement.hpp"
 #include "duckdb/parser/statement/insert_statement.hpp"
+#include "duckdb/parser/statement/prepare_statement.hpp"
 #include "duckdb/parser/statement/update_statement.hpp"
 #include "duckdb/parser/statement/select_statement.hpp"
 #endif
@@ -423,6 +424,10 @@ void StatementSimplifier::Simplify(UpdateSetInfo &info) {
 	}
 }
 
+void StatementSimplifier::Simplify(PrepareStatement &stmt) {
+	Simplify(*stmt.statement);
+}
+
 void StatementSimplifier::Simplify(UpdateStatement &stmt) {
 	Simplify(stmt.cte_map);
 	SimplifyOptional(stmt.from_table);
@@ -445,6 +450,9 @@ void StatementSimplifier::Simplify(SQLStatement &stmt) {
 	case StatementType::DELETE_STATEMENT:
 		Simplify(stmt.Cast<DeleteStatement>());
 		break;
+	case StatementType::PREPARE_STATEMENT:
+		Simplify(stmt.Cast<PrepareStatement>());
+		break;
 	default:
 		throw InvalidInputException("Expected a single SELECT, INSERT or UPDATE statement");
 	}
diff --git a/test/sql/sql_reduce.test b/test/sql/sql_reduce.test
index 1bfb3b1..428ae92 100644
--- a/test/sql/sql_reduce.test
+++ b/test/sql/sql_reduce.test
@@ -1,4 +1,4 @@
-# name: test/sql_reduce.test
+# name: test/sql/sql_reduce.test
 # description: Test reduce SQL statement
 # group: [sqlsmith]
 
@@ -77,3 +77,16 @@ DELETE FROM a WHERE (i < 5000)
 DELETE FROM a WHERE (i >= 2000)
 DELETE FROM a WHERE (i AND (i < 5000))
 DELETE FROM a WHERE NULL
+
+query I
+SELECT * FROM reduce_sql_statement('PREPARE v1 AS SELECT a, b FROM tbl') ORDER BY 1
+----
+PREPARE v1 AS SELECT NULL, b FROM tbl
+PREPARE v1 AS SELECT NULL, b FROM tbl
+PREPARE v1 AS SELECT a FROM tbl
+PREPARE v1 AS SELECT a, NULL FROM tbl
+PREPARE v1 AS SELECT a, NULL FROM tbl
+PREPARE v1 AS SELECT a, b
+PREPARE v1 AS SELECT a, b FROM tbl
+PREPARE v1 AS SELECT a, b FROM tbl
+PREPARE v1 AS SELECT b FROM tbl