removed class query and moved their static methods to simple functions

test/backends/StatementTest.cpp

@@ -40,7 +40,7 @@ protected:
 TEST_CASE_METHOD(StatementTestFixture, "Create prepared statement", "[statement]") {
   using namespace matador::utils;
   SECTION("Insert with prepared statement and placeholder") {
-    auto stmt = query::insert()
+    auto stmt = insert()
     .into(AIRPLANE, {AIRPLANE.id, AIRPLANE.brand, AIRPLANE.model})
     .values(generator::placeholders<airplane>())
     .prepare(db);
@@ -53,7 +53,7 @@ TEST_CASE_METHOD(StatementTestFixture, "Create prepared statement", "[statement]
       stmt->reset();
     }
 
-    auto result = query::select({AIRPLANE.id, AIRPLANE.brand, AIRPLANE.model})
+    auto result = select({AIRPLANE.id, AIRPLANE.brand, AIRPLANE.model})
       .from(AIRPLANE)
       .fetch_all<airplane>(db);
 
@@ -68,7 +68,7 @@ TEST_CASE_METHOD(StatementTestFixture, "Create prepared statement", "[statement]
 
   SECTION("Select with prepared statement") {
     for (const auto &plane: planes) {
-      auto res = query::insert()
+      auto res = insert()
         .into(AIRPLANE, {AIRPLANE.id, AIRPLANE.brand, AIRPLANE.model})
         .values(plane)
         .execute(db);
@@ -76,7 +76,7 @@ TEST_CASE_METHOD(StatementTestFixture, "Create prepared statement", "[statement]
       REQUIRE(res->affected_rows == 1);
     }
 
-    auto stmt = query::select({AIRPLANE.id, AIRPLANE.brand, AIRPLANE.model})
+    auto stmt = select({AIRPLANE.id, AIRPLANE.brand, AIRPLANE.model})
       .from(AIRPLANE)
       .where(AIRPLANE.brand == _)
       .prepare(db);