Query< T > Class Template Reference

This class hold a query. More...

Public Member Functions
	Query (Database *database, TableSetBase *tableSet)
QList< T * >	toList (int count=-1)
int	remove ()
T *	first ()
int	count ()
QVariant	max (FieldPhrase &f)
QVariant	min (FieldPhrase &f)
QVariant	average (FieldPhrase &f)
Query< T > *	join (const QString &tableName)
Query< T > *	setWhere (WherePhrase where)
	Where phrase is a phrase using table's static field methods.
Query< T > *	join (Table *c)
Query< T > *	orderBy (QString fieldName, QString type)
Query< T > *	orderBy (WherePhrase phrase)

Detailed Description

template<class T>
class Query< T >

This class hold a query.

A query can be used for getting database rows, editing or deleting without row fetching. A query can be used for getting data from database.

auto q = db.posts()->createQuery();
q->join(Post::commentsTable());
q->orderBy(!Post::saveDateField() & Post::bodyField());
q->setWhere(Post::idField() > 5);

auto posts = q->toList();

In below code posts is a QList<Post> that contain rows from database from this query:

SELECT * FROM post WHERE post.id>5 ORDER BY post.saveDate DESC, post.body

Member Function Documentation

template<class T >

Q_OUTOFLINE_TEMPLATE Query< T > * Query< T >::orderBy

(

WherePhrase

phrase

)

Parameters

phrase

Order phrase

Returns

This function return class itself orderBy set a new order for this query. Order can be a hrase like that:

query->orderBy(Post::idField());

If you need more than one order field seprate them by & operator, example:

query->orderBy(Post::idField() & Post::bodyField());

Order can be also DESC, for that put exclamation mark near field

query->orderBy(!Post::idField & Post::bodyField());

template<class T >

Q_OUTOFLINE_TEMPLATE Query< T > * Query< T >::setWhere

(

WherePhrase

where

)

Where phrase is a phrase using table's static field methods.

q->setWhere(Post::idField() == 4 || Post::titleField().isNull());

In sql this is like below code:

... WHERE post.id=4 OR post.title IS NULL

Parameters

where

Where phrase

Returns

This function return class itself

template<class T >

Q_OUTOFLINE_TEMPLATE QList< T * > Query< T >::toList

(

int

count = -1

)

Parameters

count

Total rows must be returned

Returns

This function return class itself This function return rows

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The documentation for this class was generated from the following files:

• src/query.h
• src/query.cpp