path: root/doc/man/man3/qsqlfieldinfo.3qt

'\" t
.TH QSqlFieldInfo 3qt "2 February 2007" "Trolltech AS" \" -*- nroff -*-
.\" Copyright 1992-2007 Trolltech ASA.  All rights reserved.  See the
.\" license file included in the distribution for a complete license
.\" statement.
.\"
.ad l
.nh
.SH NAME
QSqlFieldInfo \- Stores meta data associated with a SQL field
.SH SYNOPSIS
\fC#include <ntqsqlfield.h>\fR
.PP
.SS "Public Members"
.in +1c
.ti -1c
.BI "\fBQSqlFieldInfo\fR ( const QString & name = QString::null, QVariant::Type typ = QVariant::Invalid, int required = -1, int len = -1, int prec = -1, const QVariant & defValue = QVariant ( ), int typeID = 0, bool generated = TRUE, bool trim = FALSE, bool calculated = FALSE )"
.br
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.BI "\fBQSqlFieldInfo\fR ( const QSqlFieldInfo & other )"
.br
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.BI "\fBQSqlFieldInfo\fR ( const QSqlField & other, bool generated = TRUE )"
.br
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.BI "virtual \fB~QSqlFieldInfo\fR ()"
.br
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.BI "QSqlFieldInfo & \fBoperator=\fR ( const QSqlFieldInfo & other )"
.br
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.BI "bool \fBoperator==\fR ( const QSqlFieldInfo & f ) const"
.br
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.BI "QSqlField \fBtoField\fR () const"
.br
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.BI "int \fBisRequired\fR () const"
.br
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.BI "QVariant::Type \fBtype\fR () const"
.br
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.BI "int \fBlength\fR () const"
.br
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.BI "int \fBprecision\fR () const"
.br
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.BI "QVariant \fBdefaultValue\fR () const"
.br
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.BI "QString \fBname\fR () const"
.br
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.BI "int \fBtypeID\fR () const"
.br
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.BI "bool \fBisGenerated\fR () const"
.br
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.BI "bool \fBisTrim\fR () const"
.br
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.BI "bool \fBisCalculated\fR () const"
.br
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.BI "virtual void \fBsetTrim\fR ( bool trim )"
.br
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.BI "virtual void \fBsetGenerated\fR ( bool gen )"
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.BI "virtual void \fBsetCalculated\fR ( bool calc )"
.br
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.SH DESCRIPTION
The QSqlFieldInfo class stores meta data associated with a SQL field.
.PP
QSqlFieldInfo objects only store meta data; field values are stored in QSqlField objects.
.PP
All values must be set in the constructor, and may be retrieved using isRequired(), type(), length(), precision(), defaultValue(), name(), isGenerated() and typeID().
.PP
See also Database Classes.
.SH MEMBER FUNCTION DOCUMENTATION
.SH "QSqlFieldInfo::QSqlFieldInfo ( const QString & name = QString::null, QVariant::Type typ = QVariant::Invalid, int required = -1, int len = -1, int prec = -1, const QVariant & defValue = QVariant ( ), int typeID = 0, bool generated = TRUE, bool trim = FALSE, bool calculated = FALSE )"
Constructs a QSqlFieldInfo with the following parameters: <center>.nf
.TS
l - l. \fIname\fR the name of the field. \fItyp\fR the field's type in a QVariant. \fIrequired\fR 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. \fIlen\fR 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. \fIprec\fR the precision of the field, or -1 if the field has no precision or it cannot be determined. \fIdefValue\fR 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. \fItypeID\fR the internal typeID of the database system (only useful for low-level programming). 0 if unknown. \fIgenerated\fR TRUE indicates that this field should be included in auto-generated SQL statments, e.g. in QSqlCursor. \fItrim\fR TRUE indicates that widgets should remove trailing whitespace from character fields. This does not affect the field value but only its representation inside widgets. \fIcalculated\fR
.TE
.fi
</center>
.SH "QSqlFieldInfo::QSqlFieldInfo ( const QSqlFieldInfo & other )"
Constructs a copy of \fIother\fR.
.SH "QSqlFieldInfo::QSqlFieldInfo ( const QSqlField & other, bool generated = TRUE )"
Creates a QSqlFieldInfo object with the type and the name of the QSqlField \fIother\fR. If \fIgenerated\fR is TRUE this field will be included in auto-generated SQL statments, e.g. in QSqlCursor.
.SH "QSqlFieldInfo::~QSqlFieldInfo ()\fC [virtual]\fR"
Destroys the object and frees any allocated resources.
.SH "QVariant QSqlFieldInfo::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.
.SH "bool QSqlFieldInfo::isCalculated () const"
Returns TRUE if the field is calculated; otherwise returns FALSE.
.PP
See also setCalculated().
.SH "bool QSqlFieldInfo::isGenerated () const"
Returns TRUE if the field should be included in auto-generated SQL statments, e.g. in QSqlCursor; otherwise returns FALSE.
.PP
See also setGenerated().
.SH "int QSqlFieldInfo::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.
.SH "bool QSqlFieldInfo::isTrim () const"
Returns TRUE if trailing whitespace should be removed from character fields; otherwise returns FALSE.
.PP
See also setTrim().
.SH "int QSqlFieldInfo::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.
.SH "QString QSqlFieldInfo::name () const"
Returns the name of the field in the SQL table.
.PP
Examples:
.)l sql/overview/subclass3/main.cpp and sql/overview/subclass4/main.cpp.
.SH "QSqlFieldInfo & QSqlFieldInfo::operator= ( const QSqlFieldInfo & other )"
Assigns \fIother\fR to this field info and returns a reference to it.
.SH "bool QSqlFieldInfo::operator== ( const QSqlFieldInfo & f ) const"
Returns TRUE if this fieldinfo is equal to \fIf\fR; otherwise returns FALSE.
.PP
Two field infos are considered equal if all their attributes match.
.SH "int QSqlFieldInfo::precision () const"
Returns the field's precision or -1 if the field has no precision or it cannot be determined.
.SH "void QSqlFieldInfo::setCalculated ( bool calc )\fC [virtual]\fR"
\fIcalc\fR set to TRUE indicates that this field is a calculated field. The value of calculated fields can by modified by subclassing QSqlCursor and overriding QSqlCursor::calculateField().
.PP
See also isCalculated().
.SH "void QSqlFieldInfo::setGenerated ( bool gen )\fC [virtual]\fR"
\fIgen\fR set to FALSE indicates that this field should not appear in auto-generated SQL statements (for example in QSqlCursor).
.PP
See also isGenerated().
.SH "void QSqlFieldInfo::setTrim ( bool trim )\fC [virtual]\fR"
If \fItrim\fR is TRUE widgets should remove trailing whitespace from character fields. This does not affect the field value but only its representation inside widgets.
.PP
See also isTrim().
.SH "QSqlField QSqlFieldInfo::toField () const"
Returns an empty QSqlField based on the information in this QSqlFieldInfo.
.SH "QVariant::Type QSqlFieldInfo::type () const"
Returns the field's type or QVariant::Invalid if the type is unknown.
.SH "int QSqlFieldInfo::typeID () const"
Returns the internal type identifier as returned from the database system. The return value is 0 if the type is unknown.
.PP
\fBWarning:\fR This information is only useful for low-level database
programming and is \fInot\fR database independent.

.SH "SEE ALSO"
.BR http://doc.trolltech.com/qsqlfieldinfo.html
.BR http://www.trolltech.com/faq/tech.html
.SH COPYRIGHT
Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the
license file included in the distribution for a complete license
statement.
.SH AUTHOR
Generated automatically from the source code.
.SH BUGS
If you find a bug in Qt, please report it as described in
.BR http://doc.trolltech.com/bughowto.html .
Good bug reports help us to help you. Thank you.
.P
The definitive Qt documentation is provided in HTML format; it is
located at $QTDIR/doc/html and can be read using Qt Assistant or with
a web browser. This man page is provided as a convenience for those
users who prefer man pages, although this format is not officially
supported by Trolltech. 
.P
If you find errors in this manual page, please report them to
.BR [email protected] .
Please include the name of the manual page (qsqlfieldinfo.3qt) and the Qt
version (3.3.8).