sqlite3单例c++实现

以下是SQLite3单例C++实现的代码示例：

#include <iostream>
#include <sqlite3.h>

class SQLiteDB {
public:
    static SQLiteDB& getInstance() {
        static SQLiteDB instance;        return instance;
    }

    int open(const char* filename) {
        return sqlite3_open(filename, &db);
    }

    int close() {
        return sqlite3_close(db);
    }

    sqlite3* getDB() const {
        return db;
    }

private:
    SQLiteDB() : db(nullptr) {}
    ~SQLiteDB() {}

    SQLiteDB(const SQLiteDB&) = delete;
    SQLiteDB& operator=(const SQLiteDB&) = delete;

    sqlite3* db;
};

int main() {
    SQLiteDB& db = SQLiteDB::getInstance();
    int rc = db.open("test.db");
    if (rc) {
        std::cerr << "Can't open database: " << sqlite3_errmsg(db.getDB()) << std::endl;
        return 1;
    }
    std::cout << "Opened database successfully" << std::endl;
    db.close();
    return 0;
}