create db with sellers and articles

src/core/database.cpp

@@ -1,25 +1,62 @@
 #include "database.h"
 
 #include <stdexcept>
+#include <iostream>
 
-Database::Database(const std::string& dbname) : db(nullptr)
+Database::Database(const std::string& dbname) : db_(nullptr)
 {
-    const int errCode = sqlite3_open(dbname.c_str(), &db);
+    const int errCode = sqlite3_open(dbname.c_str(), &db_);
     if (errCode) {
         throw std::runtime_error("Could not open database file.");
     }
+    exec("PRAGMA foreign_key = 1");
 }
 
-Database::~Database() { sqlite3_close(db); }
+Database::~Database() { sqlite3_close(db_); }
 
 void Database::exec(const std::string& sql)
 {
-    const int errCode = sqlite3_exec(db, sql.c_str(), nullptr, nullptr, nullptr);
+    const int errCode = sqlite3_exec(db_, sql.c_str(), nullptr, nullptr, nullptr);
     if (errCode) {
         throw std::runtime_error("Error in SQL execution.");
     }
 }
 
+void Database::init()
+{
+    std::string sqlCreateSellers{
+        "CREATE TABLE IF NOT EXISTS sellers ("
+        "id TEXT PRIMARY KEY NOT NULL, "
+        "seller_no INTEGER, "
+        "first_name TEXT, "
+        "last_name TEXT, "
+        "offered_articles INTEGER, "
+        "UNIQUE (seller_no)"
+        ");"
+    };
+
+    std::string sqlCreateArticles{
+        "CREATE TABLE IF NOT EXISTS articles ("
+        "id TEXT PRIMARY KEY NOT NULL, "
+        "seller_id TEXT NOT NULL, "
+        "source_no INTEGER NOT NULL, "
+        "article_no INTEGER NOT NULL, "
+        "description TEXT, "
+        "price INTEGER NOT NULL, "
+        "UNIQUE (source_no, article_no), "
+        "FOREIGN KEY (seller_id) REFERENCES sellers(id) ON DELETE CASCADE, "
+        "CHECK (article_no BETWEEN 0 AND 99999)"
+        ");"
+    };
+
+    std::cout << sqlCreateArticles << "\n";
+
+    beginTransaction();
+    exec(sqlCreateSellers);
+    exec(sqlCreateArticles);
+    endTransaction();
+}
+
 void Database::beginTransaction() { exec("BEGIN TRANSACTION"); }
 
 void Database::endTransaction() { exec("END TRANSACTION"); }