likes!

server/src/db.cpp

@@ -23,7 +23,7 @@ Database::Database(const std::string& path) {
             userid INTEGER NOT NULL,
             content TEXT NOT NULL,
             timestamp INTEGER NOT NULL,
-            likes INTEGER
+            likes INTEGER NOT NULL DEFAULT 0
         );
     )";
 
@@ -158,16 +158,23 @@ void Database::addLike(uint64_t postId, uint64_t userId) {
     std::stringstream sql;
     sql << R"(
         UPDATE posts 
-        SET likes = likes + 1
+        SET likes = COALESCE(likes, 0) + 1
         WHERE id =
     )";
     sql << postId << ";";
     std::string sqlstr = sql.str();
 
-    char* errmsg = nullptr;
-    if (sqlite3_exec(db, sqlstr.c_str(), nullptr, nullptr, &errmsg) != SQLITE_OK) {
-        throw std::runtime_error("sqlite3 error: " + std::string(errmsg));
+    sqlite3_stmt* stmt;
+    if (sqlite3_prepare_v2(db, sqlstr.c_str(), -1, &stmt, nullptr) != SQLITE_OK) {
+        throw std::runtime_error("sqlite3 error: " + std::string(sqlite3_errmsg(db)));
     }
+
+    if (sqlite3_step(stmt) != SQLITE_DONE) {
+        throw std::runtime_error("sqlite3 error: " + std::string(sqlite3_errmsg(db)));
+    }
+
+    sqlite3_finalize(stmt);
+
 }