storage_t::update

template<class O>
void update(const O &o);

Update routine. Sets all non primary key fields where primary key is equal. For example if you have class/table with fields/columns [ ID, name, date, type ] then 'name', 'date' and 'type' will be updated in a row where 'ID' is equal. Note that it doesn't matter how your primary key column is named. If you try to update object of a mapped type that has no primary key on schema std::runtime_error will be thrown. To update a value without primary key please use update_all member function instead.

If there is no row with such id nothing will happen. If you want to update or insert row your should call replace member function.

Parameters

class O is an object type. May be not specified explicitly cause it can be deduced by compiler from first parameter.

(1) o is and object to be updated.

Example

#include "sqlite_orm.h"

#include <iostream>
#include <memory>

using std::cout;
using std::endl;

struct Employee {
    int id;
    std::string name;
    int age;
    std::string address;
    double salary;
};

inline auto initStorage(const std::string &path) {
    using namespace sqlite_orm;
    return make_storage(path,
                        make_table("COMPANY",
                                   make_column("ID",
                                               &Employee::id,
                                               primary_key()),
                                   make_column("NAME",
                                               &Employee::name),
                                   make_column("AGE",
                                               &Employee::age),
                                   make_column("ADDRESS",
                                               &Employee::address),
                                   make_column("SALARY",
                                               &Employee::salary)));
}

typedef decltype(initStorage("")) Storage;

static std::shared_ptr<Storage> stor;

int main(int argc, char **argv) {
    stor = std::make_shared<Storage>(initStorage("update.sqlite"));
    stor->sync_schema();
    stor->remove_all<Employee>();
    
    //  insert initial values
    stor->replace(Employee{ 1, "Paul", 32, "California", 20000.0 });
    stor->replace(Employee{ 2, "Allen", 25, "Texas", 15000.0 });
    stor->replace(Employee{ 3, "Teddy", 23, "Norway", 20000.0 });
    stor->replace(Employee{ 4, "Mark", 25, "Rich-Mond", 65000.0 });
    stor->replace(Employee{ 5, "David", 27, "Texas", 85000.0 });
    stor->replace(Employee{ 6, "Kim", 22, "South-Hall", 45000.0 });
    stor->replace(Employee{ 7, "James", 24, "Houston", 10000.0 });
    
    //  show 'COMPANY' table contents
    for(auto &employee : stor->view<Employee>()) {
        cout << stor->dump(employee) << endl;
    }
    cout << endl;
    
    //  'UPDATE COMPANY SET ADDRESS = 'Texas' WHERE ID = 6'
    
    auto employee6 = stor->get<Employee>(6);
    employee6.address = "Texas";
    stor->update(employee6);    //  actually this call updates all non-primary-key columns' values to passed object's fields
    
    //  show 'COMPANY' table contents again
    for(auto &employee : stor->view<Employee>()) {
        cout << stor->dump(employee) << endl;
    }
    cout << endl;
    
    //  'UPDATE COMPANY SET ADDRESS = 'Texas', SALARY = 20000.00 WHERE AGE < 30'
    using namespace sqlite_orm;
    stor->update_all(set(&Employee::address, "Texas",
                         &Employee::salary, 20000.00),
                     where(lesser_than(&Employee::age, 30)));
    
    //  show 'COMPANY' table contents one more time
    for(auto &employee : stor->view<Employee>()) {
        cout << stor->dump(employee) << endl;
    }
    cout << endl;
    
    return 0;
}

See also

• update_all
• replace