row_view

A non-owning read-only reference to a sequence of fields.

Synopsis

Defined in header <boost/mysql/row_view.hpp>

class row_view

Types

Name	Description
const_iterator	A random access iterator to an element.
const_reference	The reference type.
difference_type	A signed integer type used to represent differences.
iterator	A random access iterator to an element.
reference	The reference type.
size_type	An unsigned integer type to represent sizes.
value_type	A type that can hold elements in this collection with value semantics.

Member Functions

Name	Description
as_vector	Converts the row into a `std::vector` of `field`'s. — Converts the row into a `std::vector` of `field`'s.
at	Returns the i-th element in the row or throws an exception.
back	Returns the last element in the row.
begin	Returns an iterator to the first field in the row.
empty	Returns true if there are no fields in the row (i.e. `this->size() == 0`).
end	Returns an iterator to one-past-the-last field in the row.
front	Returns the first element in the row.
operator[]	Returns the i-th element in the row (unchecked access).
row_view [constructor]	Constructs an empty (but valid) view.
size	Returns the number of fields in the row.

Related Functions

Name	Description
operator==	Equality operator.
operator!=	Inequality operator.

Description

A row_view points to memory owned by an external entity (like string_view does). The validity of a row_view depends on how it was obtained:

If it was constructed from a row object (by calling row::operator row_view()), the view acts as a reference to the row's allocated memory, and is valid as long as references to that row elements are valid.
If it was obtained by indexing a rows object, the same applies.
If it was obtained by indexing a rows_view object, it's valid as long as the rows_view is valid.

Calling any member function on an invalid view results in undefined behavior.

When indexed (by using iterators, row_view::at or row_view::operator[]), it returns field_view elements that are valid as long as the underlying storage that *this points to is valid. Destroying a row_view doesn't invalidate field_views obtained from it.

Instances of this class are usually created by the library, not by the user.

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