Fixing MPI segfaults

Now everything can run smoothly with the proper run commands.

Author: Jairik

QPEMPI

@@ -215,9 +215,6 @@ int main(int argc, char *argv[]) {
 
     // Execute Queries - Distribute across MPI ranks
     for (int i = 0; i < query_count; i++) {
-        // Round-robin distribution: each rank processes queries where i % size == rank
-        if (i % size != rank) continue;
-        
         char *query = trim(queries[i]);
         if (!*query) continue;
 
@@ -234,6 +231,15 @@ int main(int argc, char *argv[]) {
 
         if (num_tokens > 0) {
             parsed = parse_tokens(tokens);
+        } else {
+            parseFailed = true;
+        }
+
+        bool is_owner = (i % size == rank);
+        bool is_collective = (parsed.command == CMD_INSERT || parsed.command == CMD_DELETE);
+        bool should_execute = is_owner || is_collective;
+
+        if (should_execute && num_tokens > 0) {
 
             // Prepare Select Items
             const char *selectItems[parsed.num_columns > 0 ? parsed.num_columns : 1];
@@ -278,16 +284,14 @@ int main(int argc, char *argv[]) {
             }
 
             execTime = MPI_Wtime() - start;
-        } else {
-            parseFailed = true;
         }
 
         // Synchronize all ranks before printing to ensure ordered output
         MPI_Barrier(MPI_COMM_WORLD);
 
         // Print results in rank order
         for (int print_rank = 0; print_rank < size; print_rank++) {
-            if (rank == print_rank) {
+            if (rank == print_rank && is_owner) {
                 printf("Executing Query: %s\n", query);
 
             if (parseFailed) {
@@ -335,11 +339,11 @@ int main(int argc, char *argv[]) {
         printf(CYAN "=================================" RESET "\n");
     }
 
-    printf("Rank %d: Freeing buffer...\n", rank);
+    // printf("Rank %d: Freeing buffer...\n", rank);
     free(buffer);
-    printf("Rank %d: Destroying engine...\n", rank);
+    // printf("Rank %d: Destroying engine...\n", rank);
     destroyEngineMPI(engine);
-    printf("Rank %d: Finalizing MPI...\n", rank);
+    // printf("Rank %d: Finalizing MPI...\n", rank);
 
     MPI_Finalize();
     return EXIT_SUCCESS;

QPEMPI.c

@@ -361,6 +361,12 @@ struct resultSetS *executeQuerySelectMPI(
     // Get all indexed attributes in the WHERE clause, using the B+ tree indexes where possible
     struct whereClauseS *wc = whereClause;
     while (wc != NULL) {
+        // Skip nested conditions for index optimization (attribute is NULL)
+        if (wc->attribute == NULL) {
+            wc = wc->next;
+            continue;
+        }
+
         for (int i = 0; i < engine->num_indexes; i++) {
             if (strcmp(wc->attribute, engine->indexed_attributes[i]) == 0) {
                 // Use B+ tree index for this attribute

QPEOMP

@@ -9,7 +9,7 @@
 
 CC       := gcc
 CSTD     := -std=c11
-CFLAGS   := $(CSTD) -Wall -Wextra -O2 -g -Iinclude
+CFLAGS   := $(CSTD) -Wall -Wextra -O2 -g -Iinclude -Wno-unused-variable  # Supress unused variable warnings
 LDFLAGS  :=
 LDLIBS   :=