DropIndex By Index Name Implementation

Implemeted the requested changes (formatting chages and proper implemetation of drop_test.cpp) by @poojanilangekar.

The same implemetation can also soleve the issue: #285

Author: dasdipanjan04

src/catalog/catalog.cpp

@@ -374,6 +374,7 @@ ResultType Catalog::CreateIndex(const std::string &database_name,
   if (txn == nullptr)
     throw CatalogException("Do not have transaction to create database " +
                            index_name);
+
   LOG_TRACE("Trying to create index %s for table %s", index_name.c_str(),
             table_name.c_str());
   // check if database exists
@@ -609,21 +610,23 @@ ResultType Catalog::DropIndex(oid_t index_oid,
 }
 
 ResultType Catalog::DropIndex(const std::string &index_name,
-                              concurrency::TransactionContext *txn){
-    if(txn == nullptr){
-        throw CatalogException("Do not have transaction to drop index " + index_name);
+                              concurrency::TransactionContext *txn) {
+    if(txn == nullptr) {
+        throw CatalogException("Do not have transaction to drop index " +
+                               index_name);
     }
-    auto index_object = catalog::IndexCatalog::GetInstance()->GetIndexObject(index_name,txn);
-    if(index_object == nullptr){
+    auto index_object = catalog::IndexCatalog::GetInstance()->GetIndexObject(
+                index_name, txn);
+    if(index_object == nullptr) {
         throw CatalogException("Index name " + index_name + " cannot be found");
     }
-    ResultType result = DropIndex(index_object->GetIndexOid(),txn);
+    ResultType result = DropIndex(index_object->GetIndexOid(), txn);
 
     return result;
 }
 
 //===--------------------------------------------------------------------===//
-// GET WITH NAME - CHECK FROM CATALOG TABLES, USING TRANSACTION             //
+// GET WITH NAME - CHECK FROM CATALOG TABLES, USING TRANSACTION
 //===--------------------------------------------------------------------===//
 
 /* Check database from pg_database with database_name using txn,

src/include/catalog/catalog.h

@@ -178,7 +178,6 @@ class Catalog {
       concurrency::TransactionContext *txn);
 
 
-
   //===--------------------------------------------------------------------===//
   // DEPRECATED FUNCTIONS
   //===--------------------------------------------------------------------===//

test/executor/drop_test.cpp

@@ -13,6 +13,7 @@
 #include <cstdio>
 
 #include "gtest/gtest.h"
+
 #include "catalog/index_catalog.h"
 #include "catalog/catalog.h"
 #include "catalog/database_catalog.h"
@@ -224,46 +225,62 @@ TEST_F(DropTests, DroppingIndexByName) {
   catalog->Bootstrap();
 
   auto &txn_manager = concurrency::TransactionManagerFactory::GetInstance();
-
   auto txn = txn_manager.BeginTransaction();
+
   catalog->CreateDatabase(TEST_DB_NAME, txn);
   auto db = catalog->GetDatabaseWithName(TEST_DB_NAME, txn);
-
   // Insert a table first
   auto id_column = catalog::Column(
       type::TypeId::INTEGER, type::Type::GetTypeSize(type::TypeId::INTEGER),
       "dept_id", true);
   auto name_column =
       catalog::Column(type::TypeId::VARCHAR, 32, "dept_name", false);
 
-
   std::unique_ptr<catalog::Schema> table_schema(
       new catalog::Schema({id_column, name_column}));
   std::unique_ptr<catalog::Schema> table_schema2(
       new catalog::Schema({id_column, name_column}));
+  txn_manager.CommitTransaction(txn);
 
-  catalog->CreateTable(TEST_DB_NAME, "department_table_01", std::move(table_schema),
-                       txn);
+  txn = txn_manager.BeginTransaction();
+  catalog->CreateTable(TEST_DB_NAME, "department_table_01",
+                       std::move(table_schema), txn);
+  txn_manager.CommitTransaction(txn);
 
+  txn = txn_manager.BeginTransaction();
   auto source_table = db->GetTableWithName("department_table_01");
-  oid_t col_id = source_table->GetSchema()->GetColumnID(id_column.column_name);
+  oid_t col_id = source_table->GetSchema()->GetColumnID(
+              id_column.column_name);
   std::vector<oid_t> source_col_ids;
   source_col_ids.push_back(col_id);
-  std::string index_name1 = "pg_table_pkey";
+  std::string index_name1 = "Testing_Drop_Index_By_Name";
   catalog->CreateIndex(TEST_DB_NAME, "department_table_01",
                        source_col_ids, index_name1, false,
                        IndexType::BWTREE, txn);
+  txn_manager.CommitTransaction(txn);
 
-  auto index_catalog = catalog::IndexCatalog::GetInstance()->GetIndexObject(index_name1, txn);
-  auto index_oid = index_catalog->GetIndexOid();
-  catalog->DropIndex(index_oid,txn);
+  txn = txn_manager.BeginTransaction();
+  auto index_catalog = catalog::IndexCatalog::GetInstance()->GetIndexObject(
+              index_name1, txn);
+  // Check the effect of drop
+  // Most major check in this test case
+  EXPECT_EQ(catalog::IndexCatalog::GetInstance()->GetIndexObject(
+                index_name1, txn), index_catalog);
 
-  std::string index_name2 = "pg_database_pkey";
-  catalog->CreateIndex(TEST_DB_NAME, "department_table_01",
-                       source_col_ids, index_name2, false,
-                       IndexType::BWTREE, txn);
-  catalog->DropIndex(index_name2,txn);
+  // Now dropping the index using the DropIndex functionality
+  catalog->DropIndex(index_name1,txn);
+  EXPECT_EQ(catalog::IndexCatalog::GetInstance()->GetIndexObject(
+                index_name1, txn), nullptr);
+  txn_manager.CommitTransaction(txn);
 
+  // Drop the table just created
+  txn = txn_manager.BeginTransaction();
+  catalog->DropTable(TEST_DB_NAME, "department_table_01", txn);
+  txn_manager.CommitTransaction(txn);
+
+  // free the database just created
+  txn = txn_manager.BeginTransaction();
+  catalog->DropDatabaseWithName(TEST_DB_NAME, txn);
   txn_manager.CommitTransaction(txn);
 }
 }  // namespace test