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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qsqlindex.h"
#include "qsqlfield.h"
#include "qstringlist.h"
QT_BEGIN_NAMESPACE
using namespace Qt::StringLiterals;
/*!
\class QSqlIndex
\brief The QSqlIndex class provides functions to manipulate and
describe database indexes.
\ingroup database
\inmodule QtSql
An \e index refers to a single table or view in a database.
Information about the fields that comprise the index can be used
to generate SQL statements.
*/
/*!
Constructs an empty index using the cursor name \a cursorname and
index name \a name.
*/
QSqlIndex::QSqlIndex(const QString& cursorname, const QString& name)
: cursor(cursorname), nm(name)
{
}
/*!
Constructs a copy of \a other.
*/
QSqlIndex::QSqlIndex(const QSqlIndex& other)
: QSqlRecord(other), cursor(other.cursor), nm(other.nm), sorts(other.sorts)
{
}
/*!
Sets the index equal to \a other.
*/
QSqlIndex& QSqlIndex::operator=(const QSqlIndex& other)
{
cursor = other.cursor;
nm = other.nm;
sorts = other.sorts;
QSqlRecord::operator=(other);
return *this;
}
/*!
Destroys the object and frees any allocated resources.
*/
QSqlIndex::~QSqlIndex()
{
}
/*!
Sets the name of the index to \a name.
*/
void QSqlIndex::setName(const QString& name)
{
nm = name;
}
/*!
\fn QString QSqlIndex::name() const
Returns the name of the index.
*/
/*!
Appends the field \a field to the list of indexed fields. The
field is appended with an ascending sort order.
*/
void QSqlIndex::append(const QSqlField& field)
{
append(field, false);
}
/*!
\overload
Appends the field \a field to the list of indexed fields. The
field is appended with an ascending sort order, unless \a desc is
true.
*/
void QSqlIndex::append(const QSqlField& field, bool desc)
{
sorts.append(desc);
QSqlRecord::append(field);
}
/*!
Returns \c true if field \a i in the index is sorted in descending
order; otherwise returns \c false.
*/
bool QSqlIndex::isDescending(int i) const
{
if (i >= 0 && i < sorts.size())
return sorts[i];
return false;
}
/*!
If \a desc is true, field \a i is sorted in descending order.
Otherwise, field \a i is sorted in ascending order (the default).
If the field does not exist, nothing happens.
*/
void QSqlIndex::setDescending(int i, bool desc)
{
if (i >= 0 && i < sorts.size())
sorts[i] = desc;
}
/*! \internal
Creates a string representing the field number \a i using prefix \a
prefix. If \a verbose is true, ASC or DESC is included in the field
description if the field is sorted in ASCending or DESCending order.
*/
QString QSqlIndex::createField(int i, const QString& prefix, bool verbose) const
{
QString f;
if (!prefix.isEmpty())
f += prefix + u'.';
f += field(i).name();
if (verbose)
f += u' ' + QString((isDescending(i) ? "DESC"_L1 : "ASC"_L1));
return f;
}
/*!
\fn QString QSqlIndex::cursorName() const
Returns the name of the cursor which the index is associated with.
*/
/*!
Sets the name of the cursor that the index is associated with to
\a cursorName.
*/
void QSqlIndex::setCursorName(const QString& cursorName)
{
cursor = cursorName;
}
QT_END_NAMESPACE
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