ASqlModel#

Defines a model that can be stored in an SQL database. Implements queries for this type to the database (insert, update, select, delete)

Header:	`#include <AUI/Data/ASqlModel.h>`
CMake:	`aui_link(my_target PUBLIC aui::data)`

Detailed Description#

Model should implement AModelMeta (see AUI/Data/AModelMeta.h)

Public Types#

NoSuchRowException#

class ASqlModel::NoSuchRowException

Thrown when a single row is expected to be received, but the database did not return any rows.

Empty structure.

TooManyRowsException#

class ASqlModel::TooManyRowsException

Thrown when one row is expected to be received, but the database returned more than one row.

Empty structure.

IncompleteSelectRequest#

class ASqlModel::IncompleteSelectRequest

Empty structure.

Public Methods#

byId#

static Model ASqlModel::byId(id_t id)

Get a row from the table by ID.

Arguments: id
ID of the required string
Returns: the string table for the specified ID \throws NoSuchRowException if no string was found for the specified ID

getIdColumnNameInOtherTables#

static AString ASqlModel::getIdColumnNameInOtherTables()

Returns: name of the relation column for other tables.

Example: struct User -> table users -> column user_id is the result.

hasMany#

template<typename Other >
_<typenameOther::IncompleteSelectRequest> ASqlModel::hasMany()

Implementation of one-to-many relation between ORM structures. Used with belongsTo.

User::getPosts() -> hasMany()

  |-- Post::getAuthor() -> belongsTo()

  |-- Post::getAuthor() -> belongsTo()

  |-- Post::getAuthor() -> belongsTo()

  ....

Returns: incomplete SQL request (see ASqlModel::IncompleteSelectRequest)

make#

template<typename . . . Args >
static Model ASqlModel::make(Args&& . . . args)

Creates a model and saves it to the database.

Arguments: args
the constructor arguments
Returns: the ORM structure

Examples:

examples/7guis/flight_booker/src/main.cpp

7GUIs Flight Booker - Flight Booker.

    // Set contents
    window->setContents(Centered {
      Vertical {
        _new<ADropdownList>(AListModel<AString>::make({ "one-way flight", "return flight" })) AUI_LET {
                AObject::connect(AUI_REACT(state->isReturnFlight ? 1 : 0), it->selectionId());
                AObject::connect(it->selectionId().changed, AObject::GENERIC_OBSERVER, [=](int newSelection) {
                    state->isReturnFlight = newSelection == 1;
                });
            },

remove#

void ASqlModel::remove()

Removes row from the table by ID.

save#

void ASqlModel::save()

Saves this model in DB. If id = 0 then a new row will be created in the table, and the id of the created row will be assigned in the structure field. If id != 0 then the existing row in the table will be updated.