diff --git a/include/operator.h b/include/operator.h
index 5a8c09e..c0c11ba 100644
--- a/include/operator.h
+++ b/include/operator.h
@@ -38,7 +38,6 @@ typedef struct SelectParams {
 typedef struct WindowParams {
     uint8_t size;
     uint8_t step;
-    bool *quit;
     source_t *source;
 } window_params_t;
 
diff --git a/include/query.h b/include/query.h
index f08ec77..5d1cee1 100644
--- a/include/query.h
+++ b/include/query.h
@@ -13,7 +13,6 @@
 
 typedef struct Query {
     struct Operator *root;
-    bool quit;
 } query_t;
 
 typedef struct {
@@ -23,7 +22,7 @@ typedef struct {
 } operator_thread_arg_t;
 
 
-void execute_query(const query_t *query, const source_t *source, sink_t *sink);
+void execute_query(const query_t *query, sink_t *sink);
 
 void join_triple_copy(const data_t *src1, uint32_t index1,
                     const data_t *src2, uint32_t index2, data_t *dest);
diff --git a/include/source.h b/include/source.h
index f5220dc..df52b7e 100644
--- a/include/source.h
+++ b/include/source.h
@@ -8,7 +8,7 @@
 // Created a source to enable other sources than generator e.g. network
 typedef struct Source {
     data_t buffer;
-    uint8_t index;
+    uint32_t index;
     uint8_t consumers;
     uint8_t consumed;
     data_t* (*get_next)(const struct Source *self, const uint8_t size, const uint8_t step);
diff --git a/src/query.c b/src/query.c
index 41445cb..dbe8b5a 100644
--- a/src/query.c
+++ b/src/query.c
@@ -6,7 +6,6 @@
 
 #include <assert.h>
 #include <stdlib.h>
-#include <pthread.h>
 
 
 /// The join operator
@@ -60,10 +59,8 @@ bool window(data_t *out, const window_params_t params)
 {
     data_t* data = params.source->get_next(params.source, params.size, params.step);
 
-    if (data == NULL) {
-        *params.quit = true;
+    if (data == NULL)
         return false;
-    }
 
     *out = *data;
     free(data);
@@ -173,13 +170,11 @@ bool execute_operator(const operator_t *operator, const data_t *in, data_t *out)
 /// @param query The query to be executed
 /// @param source The source creating the input stream
 /// @param sink The sink consuming the output stream
-void execute_query(const query_t *query, const source_t *source, sink_t *sink)
+void execute_query(const query_t *query, sink_t *sink)
 {
     data_t data = {NULL, 0, 1};
 
-    (void)source;
-    while (!query->quit) {
-        execute_operator(query->root, &data, &data);
+    while (execute_operator(query->root, &data, &data)) {
         sink->push_next(sink, &data);
     }
 }
diff --git a/tests/dataTests.cpp b/tests/dataTests.cpp
index bc87659..01fd033 100644
--- a/tests/dataTests.cpp
+++ b/tests/dataTests.cpp
@@ -163,6 +163,8 @@ TEST(DataTests, test_file_source)
     free(next_gdata);
     free(next_fdata);
 
+    ASSERT_EQ(fsource->get_next(fsource, 36, 36), nullptr);
+
     free_generator_source(gsource);
     free_file_source(fsource);
     free(gsink); // not the normal because it is still the array allocated in the lib
@@ -202,6 +204,8 @@ TEST(DataTests, test_file_source_inc)
     free(next_gdata);
     free(next_fdata);
 
+    ASSERT_EQ(fsource->get_next(fsource, increment, increment), nullptr);
+
     free_generator_source(gsource);
     free_file_source(fsource);
     free(gsink); // not the normal because it is still the array allocated int he lib
diff --git a/tests/queryTests.cpp b/tests/queryTests.cpp
index 5fe1895..253da1b 100644
--- a/tests/queryTests.cpp
+++ b/tests/queryTests.cpp
@@ -54,10 +54,10 @@ TEST_F(QueryTestFixture, test_query_join_death_no_children)
         .right = nullptr,
         .params = {.join = {.size = 1, .checks = conditions}}
     };
-    query_t query_join = {.root = &join_op, .quit = false};
+    query_t query_join = {.root = &join_op};
 
     // Program should abort because .left and .right are NULL
-    ASSERT_DEATH(execute_query(&query_join, gsource, gsink), "");
+    ASSERT_DEATH(execute_query(&query_join, gsink), "");
 }
 
 TEST_F(QueryTestFixture, test_query_join_death_no_left_child)
@@ -70,10 +70,10 @@ TEST_F(QueryTestFixture, test_query_join_death_no_left_child)
         .right = &join_op,
         .params = {.join = {.size = 1, .checks = conditions}}
     };
-    query_t query_join = {.root = &join_op, .quit = false};
+    query_t query_join = {.root = &join_op};
 
     // Program should abort because .left is NULL
-    ASSERT_DEATH(execute_query(&query_join, gsource, gsink), "");
+    ASSERT_DEATH(execute_query(&query_join, gsink), "");
 }
 
 TEST_F(QueryTestFixture, test_query_join_death_no_right_child)
@@ -86,10 +86,10 @@ TEST_F(QueryTestFixture, test_query_join_death_no_right_child)
         .right = nullptr,
         .params = {.join = {.size = 1, .checks = conditions}}
     };
-    query_t query_join = {.root = &join_op, .quit = false};
+    query_t query_join = {.root = &join_op};
 
     // Program should abort because .right is NULL
-    ASSERT_DEATH(execute_query(&query_join, gsource, gsink), "");
+    ASSERT_DEATH(execute_query(&query_join, gsink), "");
 }
 
 
@@ -100,7 +100,7 @@ bool check_filter(const triple_t in)
 
 TEST_F(QueryTestFixture, test_query_filter)
 {
-    window_params_t wparams = {36, 36, &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,  gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -116,9 +116,9 @@ TEST_F(QueryTestFixture, test_query_filter)
         .params = {.filter = {.size = 1, .checks = conditions}}
     };
 
-    gquery = {.root = &filter_op, .quit = false};
+    gquery = {.root = &filter_op};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
     triple_t expected[8] = {
         {SUBJECT_ALICE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
         {SUBJECT_BOB, PREDICATE_HAS_SKILL, OBJECT_DATA_ANALYSIS},
@@ -139,7 +139,7 @@ bool check_filter2(const triple_t in)
 
 TEST_F(QueryTestFixture, test_query_filter2)
 {
-    window_params_t wparams = {36, 36, &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,  gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -163,9 +163,9 @@ TEST_F(QueryTestFixture, test_query_filter2)
         .params = {.filter = {.size = 1, .checks = conditions2}}
     };
 
-    gquery = {.root = &filter_op2, .quit = false};
+    gquery = {.root = &filter_op2};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
     triple_t expected[4] = {
         {SUBJECT_ALICE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
         {SUBJECT_CHARLIE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
@@ -184,7 +184,7 @@ bool check_filter7(const triple_t in)
 
 TEST_F(QueryTestFixture, test_query_filter3)
 {
-    window_params_t wparams = {36, 36, &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,  gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -216,9 +216,9 @@ TEST_F(QueryTestFixture, test_query_filter3)
         .params = {.filter = {.size = 1, .checks = conditions3}}
     };
 
-    gquery = {.root = &filter_op3, .quit = false};
+    gquery = {.root = &filter_op3};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
     triple_t expected[1] = {
         {SUBJECT_ALICE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
     };
@@ -299,7 +299,7 @@ bool check_filter3(const triple_t in)
 TEST_F(QueryTestFixture, test_query_join)
 {
     source_set_comsumers(gsource, 2);
-    window_params_t wparams = {36, 36, &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,  gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -332,9 +332,9 @@ TEST_F(QueryTestFixture, test_query_join)
         .params = {.join = {.size = 1, .checks = conditions3}}
     };
 
-    gquery = {.root = &join_op, .quit = false};
+    gquery = {.root = &join_op};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
 
     triple_t expected[10] = {
         {SUBJECT_ALICE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
@@ -359,7 +359,7 @@ TEST_F(QueryTestFixture, test_query_join)
 TEST_F(QueryTestFixture, test_query_select)
 {
     source_set_comsumers(gsource, 2);
-    window_params_t wparams = {36, 36,  &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,   gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -400,9 +400,9 @@ TEST_F(QueryTestFixture, test_query_select)
         .params = {.select = {.size = 1, .colums = predicates}}
     };
 
-    gquery = {.root = &select_op, .quit = false};
+    gquery = {.root = &select_op};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
 
     triple_t expected[5] = {
         {SUBJECT_ALICE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
@@ -422,7 +422,7 @@ TEST_F(QueryTestFixture, test_query_select)
 TEST_F(QueryTestFixture, test_query_select2)
 {
     source_set_comsumers(gsource, 2);
-    window_params_t wparams = {36, 36, &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,  gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -463,9 +463,9 @@ TEST_F(QueryTestFixture, test_query_select2)
         .params = {.select = {.size = 2, .colums = predicates}}
     };
 
-    gquery = {.root = &select_op, .quit = false};
+    gquery = {.root = &select_op};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
 
     triple_t expected[10] = {
         {SUBJECT_ALICE, PREDICATE_HAS_SKILL, OBJECT_PROGRAMMING},
@@ -510,7 +510,7 @@ bool check_filter5(const triple_t in)
 TEST_F(QueryTestFixture, test_query_1)
 {
     source_set_comsumers(gsource, 3);
-    window_params_t wparams = {36, 36,  &gquery.quit, gsource};
+    window_params_t wparams = {36, 36,   gsource};
     operator_t window_op = {
         .type = WINDOW,
         .left = nullptr,
@@ -567,9 +567,9 @@ TEST_F(QueryTestFixture, test_query_1)
         .params = {.filter = {.size = 1, .checks = conditions6}}
     };
 
-    gquery = {.root = &filter_older, .quit = false};
+    gquery = {.root = &filter_older};
 
-    execute_query(&gquery, gsource, gsink);
+    execute_query(&gquery, gsink);
 
     triple_t expected[6] = {
         {SUBJECT_CHARLIE, PREDICATE_HAS_AGE, 35},