QGIS API Documentation  3.6.0-Noosa (5873452)
qgssqliteexpressioncompiler.h
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1 /***************************************************************************
2  qgssqliteexpressioncompiler.h
3  ---------------------------------
4  begin : November 2015
5  copyright : (C) 2015 Nyall Dawson
6  email : nyall dot dawson at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
16 #ifndef QGSSQLITEEXPRESSIONCOMPILER_H
17 #define QGSSQLITEEXPRESSIONCOMPILER_H
18 
19 #define SIP_NO_FILE
20 
22 
23 #include "qgis_core.h"
25 
37 class CORE_EXPORT QgsSQLiteExpressionCompiler : public QgsSqlExpressionCompiler
38 {
39  public:
40 
45  explicit QgsSQLiteExpressionCompiler( const QgsFields &fields );
46 
47  protected:
48 
49  Result compileNode( const QgsExpressionNode *node, QString &str ) override;
50  QString quotedIdentifier( const QString &identifier ) override;
51  QString quotedValue( const QVariant &value, bool &ok ) override;
52  QString sqlFunctionFromFunctionName( const QString &fnName ) const override;
53  QString castToReal( const QString &value ) const override;
54  QString castToInt( const QString &value ) const override;
55  QString castToText( const QString &value ) const override;
56 
57 };
58 
60 
61 #endif // QGSSQLITEEXPRESSIONCOMPILER_H
virtual QString castToText(const QString &value) const
Casts a value to a text result.
Container of fields for a vector layer.
Definition: qgsfields.h:42
virtual QString quotedValue(const QVariant &value, bool &ok)
Returns a quoted attribute value, in the format expected by the provider.
Abstract base class for all nodes that can appear in an expression.
Generic expression compiler for translation to provider specific SQL WHERE clauses.
virtual QString sqlFunctionFromFunctionName(const QString &fnName) const
Returns the SQL function for the expression function.
virtual QString castToInt(const QString &value) const
Casts a value to a integer result.
virtual QString castToReal(const QString &value) const
Casts a value to a real result.
virtual QString quotedIdentifier(const QString &identifier)
Returns a quoted column identifier, in the format expected by the provider.
virtual Result compileNode(const QgsExpressionNode *node, QString &str)
Compiles an expression node and returns the result of the compilation.