Function deleteBy
Summary
#include <orm_lib/inc/drogon/orm/Mapper.h>
(1) size_t deleteBy(const Criteria &criteria) noexcept(false)
(2) void deleteBy(const Criteria &criteria, const CountCallback &rcb, const ExceptionCallback &ecb) noexcept
Function overload
Synopsis
#include <orm_lib/inc/drogon/orm/Mapper.h>
size_t deleteBy(const Criteria &criteria) noexcept(false)
Description
Delete records that satisfy the given criteria.
- Parameters
criteria- The criteria.- Returns
- size_t The number of deleted records.
Source
Lines 1393-1421 in orm_lib/inc/drogon/orm/Mapper.h. Line 571 in orm_lib/inc/drogon/orm/Mapper.h.
template <typename T>
inline size_t Mapper<T>::deleteBy(const Criteria &criteria) noexcept(false)
{
clear();
static_assert(!std::is_same<typename T::PrimaryKeyType, void>::value,
"No primary key in the table!");
std::string sql = "delete from ";
sql += T::tableName;
if (criteria)
{
sql += " where ";
sql += criteria.criteriaString();
sql = replaceSqlPlaceHolder(sql, "$?");
}
Result r(nullptr);
{
auto binder = *client_ << std::move(sql);
if (criteria)
{
criteria.outputArgs(binder);
}
binder << Mode::Blocking;
binder >> [&r](const Result &result) { r = result; };
binder.exec(); // Maybe throw exception;
}
return r.affectedRows();
}
Synopsis
#include <orm_lib/inc/drogon/orm/Mapper.h>
void deleteBy(const Criteria &criteria, const CountCallback &rcb, const ExceptionCallback &ecb) noexcept
Description
Delete records that match the given criteria asynchronously.
- Parameters
criteria- The criteriarcb- is called with the number of deleted records.ecb- is called when an error occurs.
Source
Lines 1422-1447 in orm_lib/inc/drogon/orm/Mapper.h. Line 580 in orm_lib/inc/drogon/orm/Mapper.h.
template <typename T>
inline void Mapper<T>::deleteBy(const Criteria &criteria,
const CountCallback &rcb,
const ExceptionCallback &ecb) noexcept
{
clear();
static_assert(!std::is_same<typename T::PrimaryKeyType, void>::value,
"No primary key in the table!");
std::string sql = "delete from ";
sql += T::tableName;
if (criteria)
{
sql += " where ";
sql += criteria.criteriaString();
sql = replaceSqlPlaceHolder(sql, "$?");
}
auto binder = *client_ << std::move(sql);
if (criteria)
{
criteria.outputArgs(binder);
}
binder >> [rcb](const Result &r) { rcb(r.affectedRows()); };
binder >> ecb;
}