Merge pull request #333 Added Database and Statement method getChanges() from SRombauts/get-changes

Fix #331 How to get the number of updated/deleted rows?

Author: SRombauts

CHANGELOG.md

@@ -196,3 +196,4 @@ Version 3.x - 2021
 - #314 Add Database constructor for filesystem::path (#296) from ptrks
 - #295 Compile internal SQLite library with -ffunction-sections from smichaku
 - #299 Added Savepoint support from catalogm
+- #333 Added Database and Statement getChanges()

examples/example1/main.cpp

@@ -4,7 +4,7 @@
  *
  *  Demonstrates how-to use the SQLite++ wrapper
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -308,6 +308,9 @@ int main ()
         nb = db.exec("UPDATE test SET value=\"second-updated\" WHERE id='2'");
         std::cout << "UPDATE test SET value=\"second-updated\" WHERE id='2', returned " << nb << std::endl;
 
+        nb = db.getTotalChanges();
+        std::cout << "Nb of total changes since connection: " << nb << std::endl;
+
         // Check the results : expect two row of result
         SQLite::Statement   query(db, "SELECT * FROM test");
         std::cout << "SELECT * FROM test :\n";

include/SQLiteCpp/Database.h

@@ -3,7 +3,7 @@
  * @ingroup SQLiteCpp
  * @brief   Management of a SQLite Database Connection.
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -14,7 +14,7 @@
 
 // c++17: MinGW GCC version > 8
 // c++17: Visual Studio 2017 version 15.7
-#if ((__cplusplus >= 201703L) && ((!defined(__MINGW32__) && !defined(__MINGW64__)) || (__GNUC__ > 8))) || (defined(_MSVC_LANG) && (_MSVC_LANG >= 201703L))
+#if ((__cplusplus >= 201703L) && ((!defined(__MINGW32__) && !defined(__MINGW64__)) || (__GNUC__ > 8))) || (defined(_MSVC_LANG) && (_MSVC_LANG >= 201703L)) // NOLINT
 #include  <filesystem>
 #endif // c++17
 
@@ -169,7 +169,7 @@ class Database
 
     // c++17: MinGW GCC version > 8
     // c++17: Visual Studio 2017 version 15.7
-    #if ((__cplusplus >= 201703L) && ((!defined(__MINGW32__) && !defined(__MINGW64__)) || (__GNUC__ > 8))) || (defined(_MSVC_LANG) && (_MSVC_LANG >= 201703L))
+    #if ((__cplusplus >= 201703L) && ((!defined(__MINGW32__) && !defined(__MINGW64__)) || (__GNUC__ > 8))) || (defined(_MSVC_LANG) && (_MSVC_LANG >= 201703L)) // NOLINT
 
     /**
      * @brief Open the provided database std::filesystem::path.
@@ -241,7 +241,7 @@ class Database
     void setBusyTimeout(const int aBusyTimeoutMs);
 
     /**
-     * @brief Shortcut to execute one or multiple statements without results.
+     * @brief Shortcut to execute one or multiple statements without results. Return the number of changes.
      *
      *  This is useful for any kind of statements other than the Data Query Language (DQL) "SELECT" :
      *  - Data Manipulation Language (DML) statements "INSERT", "UPDATE" and "DELETE"
@@ -404,6 +404,9 @@ class Database
      */
     long long getLastInsertRowid() const noexcept;
 
+    /// Get number of rows modified by last INSERT, UPDATE or DELETE statement (not DROP table).
+    int getChanges() const noexcept;
+
     /// Get total number of rows modified by all INSERT, UPDATE or DELETE statement since connection (not DROP table).
     int getTotalChanges() const noexcept;
 

include/SQLiteCpp/Statement.h

@@ -3,7 +3,7 @@
  * @ingroup SQLiteCpp
  * @brief   A prepared SQLite Statement is a compiled SQL query ready to be executed, pointing to a row of result.
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -471,7 +471,7 @@ class Statement
     int tryExecuteStep() noexcept;
 
     /**
-     * @brief Execute a one-step query with no expected result.
+     * @brief Execute a one-step query with no expected result, and return the number of changes.
      *
      *  This method is useful for any kind of statements other than the Data Query Language (DQL) "SELECT" :
      *  - Data Definition Language (DDL) statements "CREATE", "ALTER" and "DROP"
@@ -488,7 +488,7 @@ class Statement
      *
      * @return number of row modified by this SQL statement (INSERT, UPDATE or DELETE)
      *
-     * @throw SQLite::Exception in case of error, or if row of results are returned !
+     * @throw SQLite::Exception in case of error, or if row of results are returned while they are not expected!
      */
     int exec();
 
@@ -660,6 +660,9 @@ class Statement
     const char * getColumnDeclaredType(const int aIndex) const;
 
 
+    /// Get number of rows modified by last INSERT, UPDATE or DELETE statement (not DROP table).
+    int getChanges() const noexcept;
+
 
     ////////////////////////////////////////////////////////////////////////////
 

src/Database.cpp

@@ -3,7 +3,7 @@
  * @ingroup SQLiteCpp
  * @brief   Management of a SQLite Database Connection.
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -113,6 +113,7 @@ void Database::setBusyTimeout(const int aBusyTimeoutMs)
 }
 
 // Shortcut to execute one or multiple SQL statements without results (UPDATE, INSERT, ALTER, COMMIT, CREATE...).
+// Return the number of changes.
 int Database::exec(const char* apQueries)
 {
     const int ret = tryExec(apQueries);
@@ -155,6 +156,12 @@ long long Database::getLastInsertRowid() const noexcept
     return sqlite3_last_insert_rowid(getHandle());
 }
 
+// Get number of rows modified by last INSERT, UPDATE or DELETE statement (not DROP table).
+int Database::getChanges() const noexcept
+{
+    return sqlite3_changes(getHandle());
+}
+
 // Get total number of rows modified by all INSERT, UPDATE or DELETE statement since connection.
 int Database::getTotalChanges() const noexcept
 {

src/Statement.cpp

@@ -3,7 +3,7 @@
  * @ingroup SQLiteCpp
  * @brief   A prepared SQLite Statement is a compiled SQL query ready to be executed, pointing to a row of result.
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -167,7 +167,7 @@ bool Statement::executeStep()
     return mbHasRow; // true only if one row is accessible by getColumn(N)
 }
 
-// Execute a one-step query with no expected result
+// Execute a one-step query with no expected result, and return the number of changes.
 int Statement::exec()
 {
     const int ret = tryExecuteStep();
@@ -310,6 +310,12 @@ const char * Statement::getColumnDeclaredType(const int aIndex) const
     }
 }
 
+// Get number of rows modified by last INSERT, UPDATE or DELETE statement (not DROP table).
+int Statement::getChanges() const noexcept
+{
+    return sqlite3_changes(mStmtPtr);
+}
+
 int Statement::getBindParameterCount() const noexcept
 {
     return sqlite3_bind_parameter_count(mStmtPtr);

tests/Column_test.cpp

@@ -3,7 +3,7 @@
  * @ingroup tests
  * @brief   Test of a SQLiteCpp Column.
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -44,6 +44,7 @@ TEST(Column, basis)
     // Execute the one-step query to insert the row
     EXPECT_EQ(1, insert.exec());
     EXPECT_EQ(1, db.getLastInsertRowid());
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(1, db.getTotalChanges());
 
     EXPECT_THROW(insert.exec(), SQLite::Exception); // exec() shall throw as it needs to be reseted
@@ -230,6 +231,7 @@ TEST(Column, stream)
     insert.bind(1, str);
     // Execute the one-step query to insert the row
     EXPECT_EQ(1, insert.exec());
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(1, db.getTotalChanges());
 
     SQLite::Statement query(db, "SELECT * FROM test");

tests/Database_test.cpp

@@ -3,7 +3,7 @@
  * @ingroup tests
  * @brief   Test of a SQLiteCpp Database.
  *
- * Copyright (c) 2012-2020 Sebastien Rombauts (sebastien.rombauts@gmail.com)
+ * Copyright (c) 2012-2021 Sebastien Rombauts (sebastien.rombauts@gmail.com)
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -211,32 +211,38 @@ TEST(Database, exec)
     // NOTE: here exec() returns 0 only because it is the first statements since database connexion,
     //       but its return is an undefined value for "CREATE TABLE" statements.
     db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)");
+    EXPECT_EQ(0, db.getChanges());
     EXPECT_EQ(0, db.getLastInsertRowid());
     EXPECT_EQ(0, db.getTotalChanges());
 
     // first row : insert the "first" text value into new row of id 1
     EXPECT_EQ(1, db.exec("INSERT INTO test VALUES (NULL, \"first\")"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(1, db.getLastInsertRowid());
     EXPECT_EQ(1, db.getTotalChanges());
 
     // second row : insert the "second" text value into new row of id 2
     EXPECT_EQ(1, db.exec("INSERT INTO test VALUES (NULL, \"second\")"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(2, db.getLastInsertRowid());
     EXPECT_EQ(2, db.getTotalChanges());
 
     // third row : insert the "third" text value into new row of id 3
     const std::string insert("INSERT INTO test VALUES (NULL, \"third\")");
     EXPECT_EQ(1, db.exec(insert));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(3, db.getLastInsertRowid());
     EXPECT_EQ(3, db.getTotalChanges());
 
     // update the second row : update text value to "second_updated"
     EXPECT_EQ(1, db.exec("UPDATE test SET value=\"second-updated\" WHERE id='2'"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(3, db.getLastInsertRowid()); // last inserted row ID is still 3
     EXPECT_EQ(4, db.getTotalChanges());
 
     // delete the third row
     EXPECT_EQ(1, db.exec("DELETE FROM test WHERE id='3'"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(3, db.getLastInsertRowid());
     EXPECT_EQ(5, db.getTotalChanges());
 
@@ -253,12 +259,14 @@ TEST(Database, exec)
 
     // insert two rows with two *different* statements => returns only 1, ie. for the second INSERT statement
     EXPECT_EQ(1, db.exec("INSERT INTO test VALUES (NULL, \"first\");INSERT INTO test VALUES (NULL, \"second\");"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(2, db.getLastInsertRowid());
     EXPECT_EQ(7, db.getTotalChanges());
 
 #if (SQLITE_VERSION_NUMBER >= 3007011)
     // insert two rows with only one statement (starting with SQLite 3.7.11) => returns 2
     EXPECT_EQ(2, db.exec("INSERT INTO test VALUES (NULL, \"third\"), (NULL, \"fourth\");"));
+    EXPECT_EQ(2, db.getChanges());
     EXPECT_EQ(4, db.getLastInsertRowid());
     EXPECT_EQ(9, db.getTotalChanges());
 #endif
@@ -271,32 +279,38 @@ TEST(Database, tryExec)
 
     // Create a new table with an explicit "id" column aliasing the underlying rowid
     EXPECT_EQ(SQLite::OK, db.tryExec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)"));
+    EXPECT_EQ(0, db.getChanges());
     EXPECT_EQ(0, db.getLastInsertRowid());
     EXPECT_EQ(0, db.getTotalChanges());
 
     // first row : insert the "first" text value into new row of id 1
     EXPECT_EQ(SQLite::OK, db.tryExec("INSERT INTO test VALUES (NULL, \"first\")"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(1, db.getLastInsertRowid());
     EXPECT_EQ(1, db.getTotalChanges());
 
     // second row : insert the "second" text value into new row of id 2
     EXPECT_EQ(SQLite::OK, db.tryExec("INSERT INTO test VALUES (NULL, \"second\")"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(2, db.getLastInsertRowid());
     EXPECT_EQ(2, db.getTotalChanges());
 
     // third row : insert the "third" text value into new row of id 3
     const std::string insert("INSERT INTO test VALUES (NULL, \"third\")");
     EXPECT_EQ(SQLite::OK, db.tryExec(insert));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(3, db.getLastInsertRowid());
     EXPECT_EQ(3, db.getTotalChanges());
 
     // update the second row : update text value to "second_updated"
     EXPECT_EQ(SQLite::OK, db.tryExec("UPDATE test SET value=\"second-updated\" WHERE id='2'"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(3, db.getLastInsertRowid()); // last inserted row ID is still 3
     EXPECT_EQ(4, db.getTotalChanges());
 
     // delete the third row
     EXPECT_EQ(SQLite::OK, db.tryExec("DELETE FROM test WHERE id='3'"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(3, db.getLastInsertRowid());
     EXPECT_EQ(5, db.getTotalChanges());
 
@@ -309,14 +323,16 @@ TEST(Database, tryExec)
     EXPECT_EQ(SQLite::OK, db.tryExec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)"));
     EXPECT_EQ(5, db.getTotalChanges());
 
-    // insert two rows with two *different* statements => returns only 1, ie. for the second INSERT statement
+    // insert two rows with two *different* statements => only 1 change, ie. for the second INSERT statement
     EXPECT_EQ(SQLite::OK, db.tryExec("INSERT INTO test VALUES (NULL, \"first\");INSERT INTO test VALUES (NULL, \"second\");"));
+    EXPECT_EQ(1, db.getChanges());
     EXPECT_EQ(2, db.getLastInsertRowid());
     EXPECT_EQ(7, db.getTotalChanges());
 
 #if (SQLITE_VERSION_NUMBER >= 3007011)
     // insert two rows with only one statement (starting with SQLite 3.7.11)
     EXPECT_EQ(SQLite::OK, db.tryExec("INSERT INTO test VALUES (NULL, \"third\"), (NULL, \"fourth\");"));
+    EXPECT_EQ(2, db.getChanges());
     EXPECT_EQ(4, db.getLastInsertRowid());
     EXPECT_EQ(9, db.getTotalChanges());
 #endif