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diff --git a/doc/src/classes/q3sqlfieldinfo.qdoc b/doc/src/classes/q3sqlfieldinfo.qdoc new file mode 100644 index 000000000..ba064f384 --- /dev/null +++ b/doc/src/classes/q3sqlfieldinfo.qdoc @@ -0,0 +1,234 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at http://www.qtsoftware.com/contact. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \class Q3SqlFieldInfo + \brief The Q3SqlFieldInfo class stores meta data associated with a SQL field. + + \compat + + Q3SqlFieldInfo objects only store meta data; field values are + stored in QSqlField objects. + + All values must be set in the constructor, and may be retrieved + using isRequired(), type(), length(), precision(), defaultValue(), + name(), isGenerated() and typeID(). + + \sa Q3SqlRecordInfo +*/ + +/*! + \fn Q3SqlFieldInfo::Q3SqlFieldInfo(const QString& name, + QVariant::Type typ, + int required, + int len, + int prec, + const QVariant& defValue, + int typeID, + bool generated, + bool trim, + bool calculated) + + Constructs a Q3SqlFieldInfo with the following parameters: + \table + \row \i \a name \i the name of the field. + \row \i \a typ \i the field's type in a QVariant. + \row \i \a required \i greater than 0 if the field is required, 0 + if its value can be NULL and less than 0 if it cannot be + determined whether the field is required or not. + \row \i \a len \i the length of the field. Note that for + non-character types some databases return either the length in + bytes or the number of digits. -1 signifies that the length cannot + be determined. + \row \i \a prec \i the precision of the field, or -1 if the field + has no precision or it cannot be determined. + \row \i \a defValue \i the default value that is inserted into + the table if none is specified by the user. QVariant() if there is + no default value or it cannot be determined. + \row \i \a typeID \i the internal typeID of the database system + (only useful for low-level programming). 0 if unknown. + \row \i \a generated \i TRUE indicates that this field should be + included in auto-generated SQL statments, e.g. in Q3SqlCursor. + \row \i \a trim \i TRUE indicates that widgets should remove + trailing whitespace from character fields. This does not affect + the field value but only its representation inside widgets. + \row \i \a calculated \i TRUE indicates that the value of this + field is calculated. The value of calculated fields can by + modified by subclassing Q3SqlCursor and overriding + Q3SqlCursor::calculateField(). + \endtable +*/ + +/*! + \fn Q3SqlFieldInfo::~Q3SqlFieldInfo() + + Destroys the object and frees any allocated resources. +*/ + +/*! + \fn Q3SqlFieldInfo::Q3SqlFieldInfo(const QSqlField & other) + + Creates a Q3SqlFieldInfo object with the type and the name of the + QSqlField \a other. +*/ + +/*! + \fn bool Q3SqlFieldInfo::operator==(const Q3SqlFieldInfo& other) const + + Assigns \a other to this field info and returns a reference to it. +*/ + +/*! + \fn QSqlField Q3SqlFieldInfo::toField() const + + Returns an empty QSqlField based on the information in this + Q3SqlFieldInfo. +*/ + +/*! + \fn int Q3SqlFieldInfo::isRequired() const + + Returns a value greater than 0 if the field is required (NULL + values are not allowed), 0 if it isn't required (NULL values are + allowed) or less than 0 if it cannot be determined whether the + field is required or not. +*/ + +/*! + \fn QVariant::Type Q3SqlFieldInfo::type() const + + Returns the field's type or QVariant::Invalid if the type is + unknown. +*/ + +/*! + \fn int Q3SqlFieldInfo::length() const + + Returns the field's length. For fields storing text the return + value is the maximum number of characters the field can hold. For + non-character fields some database systems return the number of + bytes needed or the number of digits allowed. If the length cannot + be determined -1 is returned. +*/ + +/*! + \fn int Q3SqlFieldInfo::precision() const + + Returns the field's precision or -1 if the field has no precision + or it cannot be determined. +*/ + +/*! + \fn QVariant Q3SqlFieldInfo::defaultValue() const + + Returns the field's default value or an empty QVariant if the + field has no default value or the value couldn't be determined. + The default value is the value inserted in the database when it + is not explicitly specified by the user. +*/ + +/*! + \fn QString Q3SqlFieldInfo::name() const + + Returns the name of the field in the SQL table. +*/ + +/*! + \fn int Q3SqlFieldInfo::typeID() const + + Returns the internal type identifier as returned from the database + system. The return value is 0 if the type is unknown. +*/ + +/*! + \fn bool Q3SqlFieldInfo::isGenerated() const + + Returns TRUE if the field should be included in auto-generated + SQL statments, e.g. in Q3SqlCursor; otherwise returns FALSE. + + \sa setGenerated() +*/ + +/*! + \fn bool Q3SqlFieldInfo::isTrim() const + + Returns TRUE if trailing whitespace should be removed from + character fields; otherwise returns FALSE. + + \sa setTrim() +*/ + +/*! + \fn bool Q3SqlFieldInfo::isCalculated() const + + Returns TRUE if the field is calculated; otherwise returns FALSE. + + \sa setCalculated() +*/ + +/*! + \fn void Q3SqlFieldInfo::setTrim(bool trim) + + If \a trim is TRUE widgets should remove trailing whitespace from + character fields. This does not affect the field value but only + its representation inside widgets. + + \sa isTrim() +*/ + +/*! + \fn void Q3SqlFieldInfo::setGenerated(bool generated) + + \a generated set to FALSE indicates that this field should not appear + in auto-generated SQL statements (for example in Q3SqlCursor). + + \sa isGenerated() +*/ + +/*! + \fn void Q3SqlFieldInfo::setCalculated(bool calculated) + + \a calculated set to TRUE indicates that this field is a calculated + field. The value of calculated fields can by modified by subclassing + Q3SqlCursor and overriding Q3SqlCursor::calculateField(). + + \sa isCalculated() +*/ |