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qgsspatialiteprovider.cpp
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qgsspatialiteprovider.cpp
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/***************************************************************************
qgsspatialiteprovider.cpp Data provider for SpatiaLite DBMS
begin : Dec, 2008
copyright : (C) 2008 Sandro Furieri
email : a.furieri@lqt.it
***************************************************************************/
/***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************/
#include <cassert>
#include <qgis.h>
#include <qgsapplication.h>
#include <qgsfeature.h>
#include <qgsfield.h>
#include <qgsgeometry.h>
#include <qgsmessageoutput.h>
#include <qgsrectangle.h>
#include <qgscoordinatereferencesystem.h>
#include "qgsprovidercountcalcevent.h"
#include "qgsproviderextentcalcevent.h"
#include "qgsspatialiteprovider.h"
#include "qgslogger.h"
#ifdef _MSC_VER
#define strcasecmp(a,b) stricmp(a,b)
#endif
const QString SPATIALITE_KEY = "spatialite";
const QString SPATIALITE_DESCRIPTION = "SpatiaLite data provider";
QMap < QString, QgsSpatiaLiteProvider::SqliteHandles * >QgsSpatiaLiteProvider::SqliteHandles::handles;
QgsSpatiaLiteProvider::QgsSpatiaLiteProvider( QString const &uri ): QgsVectorDataProvider( uri ),
geomType( QGis::WKBUnknown ), sqliteHandle( NULL ), sqliteStatement( NULL ), mSrid( -1 ), spatialIndexRTree( false ), spatialIndexMbrCache( false )
{
QgsDataSourceURI mUri = QgsDataSourceURI( uri );
// parsing members from the uri structure
mTableName = mUri.table();
geometryColumn = mUri.geometryColumn();
// extracting the DB path
int idx = uri.indexOf( "dbname='" );
if ( idx >= 0 )
mSqlitePath = uri.mid( idx + 8 );
else
mSqlitePath = uri;
idx = mSqlitePath.indexOf( "' table=" );
if ( idx > 0 )
mSqlitePath.truncate( idx );
// trying to open the SQLite DB
spatialite_init( 0 );
valid = true;
handle = SqliteHandles::openDb( mSqlitePath );
if ( handle == NULL )
{
valid = false;
return;
}
sqliteHandle = handle->handle();
enabledCapabilities = QgsVectorDataProvider::SelectAtId | QgsVectorDataProvider::SelectGeometryAtId;
enabledCapabilities |= QgsVectorDataProvider::DeleteFeatures;
enabledCapabilities |= QgsVectorDataProvider::ChangeGeometries;
enabledCapabilities |= QgsVectorDataProvider::ChangeAttributeValues;
enabledCapabilities |= QgsVectorDataProvider::AddFeatures;
enabledCapabilities |= QgsVectorDataProvider::AddAttributes;
if ( !getGeometryDetails() ) // gets srid and geometry type
{
// the table is not a geometry table
numberFeatures = 0;
valid = false;
QgsLogger::critical( "Invalid SpatiaLite layer" );
closeDb();
return;
}
if ( !getTableSummary() ) // gets the extent and feature count
{
numberFeatures = 0;
valid = false;
QgsLogger::critical( "Invalid SpatiaLite layer" );
closeDb();
return;
}
// load the columns list
loadFields();
if ( sqliteHandle == NULL )
{
valid = false;
QgsLogger::critical( "Invalid SpatiaLite layer" );
return;
}
//fill type names into sets
mNativeTypes
<< QgsVectorDataProvider::NativeType( tr( "BLOB" ), "SQLITE_BLOB", QVariant::ByteArray )
<< QgsVectorDataProvider::NativeType( tr( "Text" ), "SQLITE_TEXT", QVariant::String )
<< QgsVectorDataProvider::NativeType( tr( "Double" ), "SQLITE_FLOAT", QVariant::Double, 0, 20, 0, 20 )
<< QgsVectorDataProvider::NativeType( tr( "Integer" ), "SQLITE_INTEGER", QVariant::LongLong, 0, 20 )
;
}
QgsSpatiaLiteProvider::~QgsSpatiaLiteProvider()
{
closeDb();
}
void QgsSpatiaLiteProvider::loadFields()
{
int ret;
int i;
char **results;
int rows;
int columns;
char *errMsg = NULL;
QString pkName;
int pkCount = 0;
char xSql[1024];
attributeFields.clear();
primaryKey.clear();
QString sql = QString( "PRAGMA table_info(%1)" ).arg( quotedValue( mTableName ) );
strcpy( xSql, sql.toUtf8().constData() );
ret = sqlite3_get_table( sqliteHandle, xSql, &results, &rows, &columns, &errMsg );
if ( ret != SQLITE_OK )
goto error;
if ( rows < 1 )
;
else
{
for ( i = 1; i <= rows; i++ )
{
QString name = results[( i * columns ) + 1];
const char *type = results[( i * columns ) + 2];
QString pk = results[( i * columns ) + 5];
if ( pk.toInt() != 0 )
{
// found a Primary Key column
pkCount++;
pkName = name;
}
if ( name != geometryColumn )
{
// for sure any SQLite value can be represented as SQLITE_TEXT
QVariant::Type fieldType = QVariant::String;
// making some assumptions in order to guess a more realistic type
if ( strcasecmp( type, "int" ) == 0 ||
strcasecmp( type, "integer" ) == 0 ||
strcasecmp( type, "bigint" ) == 0 ||
strcasecmp( type, "smallint" ) == 0 || strcasecmp( type, "tinyint" ) == 0 || strcasecmp( type, "boolean" ) == 0 )
{
fieldType = QVariant::Int;
}
else if ( strcasecmp( type, "real" ) == 0 ||
strcasecmp( type, "double" ) == 0 ||
strcasecmp( type, "double precision" ) == 0 || strcasecmp( type, "float" ) == 0 )
{
fieldType = QVariant::Double;
}
attributeFields.insert( i - 1, QgsField( name, fieldType, type, 0, 0, "" ) );
}
}
}
sqlite3_free_table( results );
if ( pkCount == 1 )
{
// setting the Primary Key column name
primaryKey = pkName;
}
return;
error:
// unexpected error
if ( errMsg != NULL )
{
QString error = "loadFields() SQL error: ";
error = errMsg;
QgsLogger::critical( error );
sqlite3_free( errMsg );
}
}
QString QgsSpatiaLiteProvider::storageType() const
{
return "SQLite database with SpatiaLite extension";
}
bool QgsSpatiaLiteProvider::featureAtId( int featureId, QgsFeature & feature, bool fetchGeometry, QgsAttributeList fetchAttributes )
{
sqlite3_stmt *stmt = NULL;
char xSql[1024];
char geomName[128];
QString sql = "SELECT ROWID";
for ( QgsAttributeList::const_iterator it = fetchAttributes.constBegin(); it != fetchAttributes.constEnd(); ++it )
{
const QgsField & fld = field( *it );
const QString & fieldname = fld.name();
sql += ", ";
sql += fieldname;
}
if ( fetchGeometry )
{
sql += QString( ", AsBinary(%1)" ).arg( geometryColumn );
}
sql += QString( " FROM %1 WHERE ROWID = %2" ).arg( quotedValue( mTableName ) ).arg( featureId );
strcpy( xSql, sql.toUtf8().constData() );
if ( sqlite3_prepare_v2( sqliteHandle, xSql, strlen( xSql ), &stmt, NULL ) != SQLITE_OK )
{
// some error occurred
QString errCause = sqlite3_errmsg( sqliteHandle );
QString msg = tr( "SQLite error: %1\n\nSQL: %2" ).arg( sql ).arg( errCause );
QgsLogger::critical( msg );
return false;
}
int ret = sqlite3_step( stmt );
if ( ret == SQLITE_DONE )
{
// there are no more rows to fetch - we can stop looping destroying the SQLite statement
sqlite3_finalize( stmt );
return false;
}
if ( ret == SQLITE_ROW )
{
// one valid row has been fetched from the result set
if ( !mFetchGeom )
{
// no geometry was required
feature.setGeometryAndOwnership( 0, 0 );
}
int ic;
int n_columns = sqlite3_column_count( stmt );
for ( ic = 0; ic < n_columns; ic++ )
{
if ( ic == 0 )
{
// first column always contains the ROWID
feature.setFeatureId( sqlite3_column_int( stmt, ic ) );
}
else
{
// iterate attributes
bool fetched = false;
int nAttr = 1;
for ( QgsAttributeList::const_iterator it = mAttributesToFetch.constBegin(); it != mAttributesToFetch.constEnd(); it++ )
{
if ( nAttr == ic )
{
// ok, this one is the corresponding attribure
if ( sqlite3_column_type( stmt, ic ) == SQLITE_INTEGER )
{
// INTEGER value
feature.addAttribute( *it, sqlite3_column_int( stmt, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( stmt, ic ) == SQLITE_FLOAT )
{
// DOUBLE value
feature.addAttribute( *it, sqlite3_column_double( stmt, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( stmt, ic ) == SQLITE_TEXT )
{
// TEXT value
const char *txt = ( const char * ) sqlite3_column_text( stmt, ic );
QString str = QString::fromUtf8( txt );
feature.addAttribute( *it, str );
fetched = true;
}
else
{
// assuming NULL
feature.addAttribute( *it, QVariant( QString::null ) );
fetched = true;
}
}
nAttr++;
}
if ( fetched )
{
continue;
}
if ( mFetchGeom )
{
QString geoCol = QString( "AsBinary(%1)" ).arg( geometryColumn );
strcpy( geomName, geoCol.toUtf8().constData() );
if ( strcasecmp( geomName, sqlite3_column_name( stmt, ic ) ) == 0 )
{
if ( sqlite3_column_type( stmt, ic ) == SQLITE_BLOB )
{
const void *blob = sqlite3_column_blob( stmt, ic );
size_t blob_size = sqlite3_column_bytes( stmt, ic );
unsigned char *featureGeom = new unsigned char[blob_size + 1];
memset( featureGeom, '\0', blob_size + 1 );
memcpy( featureGeom, blob, blob_size );
feature.setGeometryAndOwnership( featureGeom, blob_size + 1 );
}
else
{
// NULL geometry
feature.setGeometryAndOwnership( 0, 0 );
}
}
}
}
}
}
else
{
// some unexpected error occurred
QString error = "sqlite3_step() error: ";
error += sqlite3_errmsg( sqliteHandle );
QgsLogger::critical( error );
sqlite3_finalize( stmt );
return false;
}
sqlite3_finalize( stmt );
return true;
}
bool QgsSpatiaLiteProvider::nextFeature( QgsFeature & feature )
{
char geomName[128];
feature.setValid( false );
if ( !valid )
{
QgsLogger::critical( "Read attempt on an invalid SpatiaLite data source" );
return false;
}
if ( sqliteStatement == NULL )
{
QgsLogger::critical( "Invalid current SQLite statement" );
return false;
}
int ret = sqlite3_step( sqliteStatement );
if ( ret == SQLITE_DONE )
{
// there are no more rows to fetch - we can stop looping destroying the SQLite statement
sqlite3_finalize( sqliteStatement );
sqliteStatement = NULL;
return false;
}
if ( ret == SQLITE_ROW )
{
// one valid row has been fetched from the result set
if ( !mFetchGeom )
{
// no geometry was required
feature.setGeometryAndOwnership( 0, 0 );
}
int ic;
int n_columns = sqlite3_column_count( sqliteStatement );
for ( ic = 0; ic < n_columns; ic++ )
{
if ( ic == 0 )
{
// first column always contains the ROWID
feature.setFeatureId( sqlite3_column_int( sqliteStatement, ic ) );
}
else
{
// iterate attributes
bool fetched = false;
int nAttr = 1;
for ( QgsAttributeList::const_iterator it = mAttributesToFetch.constBegin(); it != mAttributesToFetch.constEnd(); it++ )
{
if ( nAttr == ic )
{
// ok, this one is the corresponding attribure
if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_INTEGER )
{
// INTEGER value
feature.addAttribute( *it, sqlite3_column_int( sqliteStatement, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_FLOAT )
{
// DOUBLE value
feature.addAttribute( *it, sqlite3_column_double( sqliteStatement, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_TEXT )
{
// TEXT value
const char *txt = ( const char * ) sqlite3_column_text( sqliteStatement, ic );
QString str = QString::fromUtf8( txt );
feature.addAttribute( *it, str );
fetched = true;
}
else
{
// assuming NULL
feature.addAttribute( *it, QVariant( QString::null ) );
fetched = true;
}
}
nAttr++;
}
if ( fetched )
{
continue;
}
if ( mFetchGeom )
{
QString geoCol = QString( "AsBinary(%1)" ).arg( geometryColumn );
strcpy( geomName, geoCol.toUtf8().constData() );
if ( strcasecmp( geomName, sqlite3_column_name( sqliteStatement, ic ) ) == 0 )
{
if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_BLOB )
{
const void *blob = sqlite3_column_blob( sqliteStatement, ic );
size_t blob_size = sqlite3_column_bytes( sqliteStatement, ic );
unsigned char *featureGeom = new unsigned char[blob_size + 1];
memset( featureGeom, '\0', blob_size + 1 );
memcpy( featureGeom, blob, blob_size );
feature.setGeometryAndOwnership( featureGeom, blob_size + 1 );
}
else
{
// NULL geometry
feature.setGeometryAndOwnership( 0, 0 );
}
}
}
}
}
}
else
{
// some unexpected error occurred
QString error = "sqlite3_step() error: ";
error += sqlite3_errmsg( sqliteHandle );
QgsLogger::critical( error );
sqlite3_finalize( sqliteStatement );
sqliteStatement = NULL;
return false;
}
feature.setValid( true );
return true;
}
void QgsSpatiaLiteProvider::select( QgsAttributeList fetchAttributes, QgsRectangle rect, bool fetchGeometry, bool useIntersect )
{
// preparing the SQL statement
char xSql[1024];
if ( !valid )
{
QgsLogger::critical( "Read attempt on an invalid SpatiaLite data source" );
return;
}
if ( sqliteStatement != NULL )
{
// finalizing the current SQLite statement
sqlite3_finalize( sqliteStatement );
sqliteStatement = NULL;
}
QString sql = "SELECT ROWID";
for ( QgsAttributeList::const_iterator it = fetchAttributes.constBegin(); it != fetchAttributes.constEnd(); ++it )
{
const QgsField & fld = field( *it );
const QString & fieldname = fld.name();
sql += ", ";
sql += fieldname;
}
if ( fetchGeometry )
{
sql += QString( ", AsBinary(%1)" ).arg( geometryColumn );
}
sql += QString( " FROM %1" ).arg( quotedValue( mTableName ) );
QString whereClause;
if ( !rect.isEmpty() )
{
// some kind of MBR spatial filtering is required
whereClause = " WHERE ";
if ( useIntersect )
{
// we are requested to evaluate a true INTERSECT relationship
QString mbr = QString( "%1, %2, %3, %4" ).
arg( QString::number( rect.xMinimum(), 'f', 6 ) ).
arg( QString::number( rect.yMinimum(), 'f', 6 ) ).
arg( QString::number( rect.xMaximum(), 'f', 6 ) ).arg( QString::number( rect.yMaximum(), 'f', 6 ) );
whereClause += QString( "Intersects(%1, BuildMbr(%2)) AND " ).arg( geometryColumn ).arg( mbr );
}
if ( spatialIndexRTree )
{
// using the RTree spatial index
QString mbrFilter = QString( "xmin <= %1 AND " ).arg( QString::number( rect.xMaximum(), 'f', 6 ) );
mbrFilter += QString( "xmax >= %1 AND " ).arg( QString::number( rect.xMinimum(), 'f', 6 ) );
mbrFilter += QString( "ymin <= %1 AND " ).arg( QString::number( rect.yMaximum(), 'f', 6 ) );
mbrFilter += QString( "ymax >= %1" ).arg( QString::number( rect.yMinimum(), 'f', 6 ) );
QString idxName = QString( "idx_%1_%2" ).arg( mTableName ).arg( geometryColumn );
whereClause += QString( "ROWID IN (SELECT pkid FROM %1 WHERE %2)" ).arg( idxName ).arg( mbrFilter );
}
else if ( spatialIndexMbrCache )
{
// using the MbrCache spatial index
QString mbr = QString( "%1, %2, %3, %4" ).
arg( QString::number( rect.xMinimum(), 'f', 6 ) ).
arg( QString::number( rect.yMinimum(), 'f', 6 ) ).
arg( QString::number( rect.xMaximum(), 'f', 6 ) ).arg( QString::number( rect.yMaximum(), 'f', 6 ) );
QString idxName = QString( "cache_%1_%2" ).arg( mTableName ).arg( geometryColumn );
whereClause += QString( "ROWID IN (SELECT rowid FROM %1 WHERE mbr = FilterMbrIntersects(%2))" ).arg( idxName ).arg( mbr );
}
else
{
// using simple MBR filtering
QString mbr = QString( "%1, %2, %3, %4" ).
arg( QString::number( rect.xMinimum(), 'f', 6 ) ).
arg( QString::number( rect.yMinimum(), 'f', 6 ) ).
arg( QString::number( rect.xMaximum(), 'f', 6 ) ).arg( QString::number( rect.yMaximum(), 'f', 6 ) );
whereClause += QString( "MbrIntersects(%1, BuildMbr(%2))" ).arg( geometryColumn ).arg( mbr );
}
}
if ( !whereClause.isEmpty() )
sql += whereClause;
mFetchGeom = fetchGeometry;
mAttributesToFetch = fetchAttributes;
strcpy( xSql, sql.toUtf8().constData() );
if ( sqlite3_prepare_v2( sqliteHandle, xSql, strlen( xSql ), &sqliteStatement, NULL ) != SQLITE_OK )
{
// some error occurred
QString errCause = sqlite3_errmsg( sqliteHandle );
QString msg = tr( "SQLite error: %1\n\nSQL: %2" ).arg( sql ).arg( errCause );
QgsLogger::critical( msg );
sqliteStatement = NULL;
valid = false;
}
}
QgsRectangle QgsSpatiaLiteProvider::extent()
{
return layerExtent;
}
size_t QgsSpatiaLiteProvider::layerCount() const
{
return 1;
}
/**
* Return the feature type
*/
QGis::WkbType QgsSpatiaLiteProvider::geometryType() const
{
return geomType;
}
/**
* Return the feature type
*/
long QgsSpatiaLiteProvider::featureCount() const
{
return numberFeatures;
}
/**
* Return the number of fields
*/
uint QgsSpatiaLiteProvider::fieldCount() const
{
return attributeFields.size();
}
void QgsSpatiaLiteProvider::rewind()
{
if ( sqliteStatement )
{
sqlite3_finalize( sqliteStatement );
sqliteStatement = NULL;
}
loadFields();
}
QgsCoordinateReferenceSystem QgsSpatiaLiteProvider::crs()
{
QgsCoordinateReferenceSystem srs;
srs.createFromProj4( mProj4text );
return srs;
}
bool QgsSpatiaLiteProvider::isValid()
{
return valid;
}
QString QgsSpatiaLiteProvider::name() const
{
return SPATIALITE_KEY;
} // QgsSpatiaLiteProvider::name()
QString QgsSpatiaLiteProvider::description() const
{
return SPATIALITE_DESCRIPTION;
} // QgsSpatiaLiteProvider::description()
const QgsFieldMap & QgsSpatiaLiteProvider::fields() const
{
return attributeFields;
}
// Returns the minimum value of an attribute
QVariant QgsSpatiaLiteProvider::minimumValue( int index )
{
int ret;
int i;
char **results;
int rows;
int columns;
char *errMsg = NULL;
QString minValue;
char xSql[1024];
// get the field name
const QgsField & fld = field( index );
QString sql = QString( "SELECT Min(%1) FROM %2" ).arg( fld.name() ).arg( quotedValue( mTableName ) );
strcpy( xSql, sql.toUtf8().constData() );
ret = sqlite3_get_table( sqliteHandle, xSql, &results, &rows, &columns, &errMsg );
if ( ret != SQLITE_OK )
goto error;
if ( rows < 1 )
;
else
{
for ( i = 1; i <= rows; i++ )
{
minValue = results[( i * columns ) + 0];
}
}
sqlite3_free_table( results );
if ( minValue.isEmpty() )
{
// NULL or not found
return QVariant( QString::null );
}
else
{
// returning as DOUBLE
return minValue.toDouble();
}
error:
// unexpected error
if ( errMsg != NULL )
{
QString error = "minValue() SQL error: ";
error = errMsg;
QgsLogger::critical( error );
sqlite3_free( errMsg );
}
return QVariant( QString::null );
}
// Returns the maximum value of an attribute
QVariant QgsSpatiaLiteProvider::maximumValue( int index )
{
int ret;
int i;
char **results;
int rows;
int columns;
char *errMsg = NULL;
QString maxValue;
char xSql[1024];
// get the field name
const QgsField & fld = field( index );
QString sql = QString( "SELECT Max(%1) FROM %2" ).arg( fld.name() ).arg( quotedValue( mTableName ) );
strcpy( xSql, sql.toUtf8().constData() );
ret = sqlite3_get_table( sqliteHandle, xSql, &results, &rows, &columns, &errMsg );
if ( ret != SQLITE_OK )
goto error;
if ( rows < 1 )
;
else
{
for ( i = 1; i <= rows; i++ )
{
maxValue = results[( i * columns ) + 0];
}
}
sqlite3_free_table( results );
if ( maxValue.isEmpty() )
{
// NULL or not found
return QVariant( QString::null );
}
else
{
// returning as DOUBLE
return maxValue.toDouble();
}
error:
// unexpected error
if ( errMsg != NULL )
{
QString error = "maxValue() SQL error: ";
error = errMsg;
QgsLogger::critical( error );
sqlite3_free( errMsg );
}
return QVariant( QString::null );
}
// Returns the list of unique values of an attribute
void QgsSpatiaLiteProvider::uniqueValues( int index, QList < QVariant > &uniqueValues )
{
sqlite3_stmt *stmt = NULL;
char *errMsg = NULL;
QString sql;
QString txt;
char xSql[1024];
uniqueValues.clear();
// get the field name
const QgsField & fld = field( index );
sql = QString( "SELECT DISTINCT %1 FROM %2 ORDER BY %1" ).arg( fld.name() ).arg( quotedValue( mTableName ) );
// SQLite prepared statement
strcpy( xSql, sql.toUtf8().constData() );
if ( sqlite3_prepare_v2( sqliteHandle, xSql, strlen( xSql ), &stmt, NULL ) != SQLITE_OK )
{
// some error occurred
QString errCause = sqlite3_errmsg( sqliteHandle );
QString msg = tr( "SQLite error: %1\n\nSQL: %2" ).arg( sql ).arg( errCause );
QgsLogger::critical( msg );
return;
}
while ( 1 )
{
// this one is an infinitive loop, intended to fetch any row
int ret = sqlite3_step( stmt );
if ( ret == SQLITE_DONE )
{
// there are no more rows to fetch - we can stop looping
break;
}
if ( ret == SQLITE_ROW )
{
// fetching one column value
switch ( sqlite3_column_type( stmt, 0 ) )
{
case SQLITE_INTEGER:
uniqueValues.append( QString( "%1" ).arg( sqlite3_column_int( stmt, 0 ) ) );
break;
case SQLITE_FLOAT:
uniqueValues.append( QString( "%1" ).arg( sqlite3_column_double( stmt, 0 ) ) );
break;
case SQLITE_TEXT:
txt = ( const char * ) sqlite3_column_text( stmt, 0 );
uniqueValues.append( txt );
break;
default:
txt = "";
uniqueValues.append( txt );
break;
};
}
else
{
// some unexpected error occurred
const char *err = sqlite3_errmsg( sqliteHandle );
int len = strlen( err );
errMsg = ( char * ) sqlite3_malloc( len + 1 );
strcpy( errMsg, err );
goto abort;
}
}
sqlite3_finalize( stmt );
return;
abort:
QString msg = QString( "getUniqueValues SQL error:\n%1\n" ).arg( sql );
if ( errMsg )
{
msg += errMsg;
sqlite3_free( errMsg );
}
else
msg += "unknown cause";
QgsLogger::critical( msg );
}
bool QgsSpatiaLiteProvider::addFeatures( QgsFeatureList & flist )
{
sqlite3_stmt *stmt = NULL;
char *errMsg = NULL;
bool toCommit = false;
QString sql;
QString values;
int ia;
char xSql[1024];
if ( flist.size() == 0 )
return true;
const QgsAttributeMap & attributevec = flist[0].attributeMap();
strcpy( xSql, "BEGIN" );
int ret = sqlite3_exec( sqliteHandle, xSql, NULL, NULL, &errMsg );
if ( ret != SQLITE_OK )
{
// some error occurred
goto abort;
}
toCommit = true;
if ( !primaryKey.isEmpty() )
{
sql = QString( "INSERT INTO %1 (%2, %3" ).
arg( quotedValue( mTableName ) ).arg( quotedValue( primaryKey ) ).arg( quotedValue( geometryColumn ) );
values = QString( ") VALUES (NULL, GeomFromWKB(?, %1)" ).arg( mSrid );
}
else
{
sql = QString( "INSERT INTO %1 (%2" ).arg( quotedValue( mTableName ) ).arg( quotedValue( geometryColumn ) );
values = QString( ") VALUES (GeomFromWKB(?, %1)" ).arg( mSrid );
}
for ( QgsAttributeMap::const_iterator it = attributevec.begin(); it != attributevec.end(); it++ )
{
QgsFieldMap::const_iterator fit = attributeFields.find( it.key() );
if ( fit == attributeFields.end() )
continue;
QString fieldname = fit->name();
if ( fieldname.isEmpty() || fieldname == geometryColumn || fieldname == primaryKey )
continue;
sql += ", ";
sql += quotedValue( fieldname );
values += ", ?";
}
sql += values;
sql += ")";
// SQLite prepared statement
strcpy( xSql, sql.toUtf8().constData() );
if ( sqlite3_prepare_v2( sqliteHandle, xSql, strlen( xSql ), &stmt, NULL ) != SQLITE_OK )
{
// some error occurred
QString errCause = sqlite3_errmsg( sqliteHandle );
QString msg = tr( "SQLite error: %1\n\nSQL: %2" ).arg( sql ).arg( errCause );
QgsLogger::critical( msg );
return false;
}
for ( QgsFeatureList::iterator features = flist.begin(); features != flist.end(); features++ )
{
// looping on each feature to insert
const QgsAttributeMap & attributevec = features->attributeMap();
// resetting Prepared Statement and bindings
sqlite3_reset( stmt );
sqlite3_clear_bindings( stmt );
// binding GEOMETRY to Prepared Statement
const unsigned char *wkb = features->geometry()->asWkb();
sqlite3_bind_blob( stmt, 1, wkb, features->geometry()->wkbSize(), SQLITE_STATIC );
// initializing the column counter
ia = 1;
for ( QgsAttributeMap::const_iterator it = attributevec.begin(); it != attributevec.end(); it++ )
{
// binding values for each attribute
QgsFieldMap::const_iterator fit = attributeFields.find( it.key() );
if ( fit == attributeFields.end() )
continue;
QString fieldname = fit->name();
if ( fieldname.isEmpty() || fieldname == geometryColumn || fieldname == primaryKey )
continue;
QVariant::Type type = fit->type();
if ( it->toString().isEmpty() )
{
// assuming to be a NULL value
type = QVariant::Invalid;
}
if ( type == QVariant::Int )
{
// binding an INTEGER value
sqlite3_bind_int( stmt, ++ia, it->toInt() );
}
else if ( type == QVariant::Double )
{
// binding a DOUBLE value
sqlite3_bind_double( stmt, ++ia, it->toDouble() );
}
else if ( type == QVariant::String )
{
// binding a TEXT value
QString txt = it->toString();
int len = txt.length();
char *vl = new char [len];
strcpy( vl, txt.toUtf8().constData() );
sqlite3_bind_text( stmt, ++ia, vl, len, SQLITE_TRANSIENT );
delete [] vl;
}
else
{
// binding a NULL value
sqlite3_bind_null( stmt, ++ia );
}
}
// performing actual row insert
ret = sqlite3_step( stmt );
if ( ret == SQLITE_DONE || ret == SQLITE_ROW )
;
else
{
// some unexpected error occurred
const char *err = sqlite3_errmsg( sqliteHandle );
int len = strlen( err );
errMsg = ( char * ) sqlite3_malloc( len + 1 );
strcpy( errMsg, err );
goto abort;
}
}
sqlite3_finalize( stmt );
strcpy( xSql, "COMMIT" );
ret = sqlite3_exec( sqliteHandle, xSql, NULL, NULL, &errMsg );
if ( ret != SQLITE_OK )
{
// some error occurred
goto abort;
}
return true;
abort:
QString msg = QString( "addFeatures SQL error:\n%1\n" ).arg( sql );
if ( errMsg )
{
msg += errMsg;
sqlite3_free( errMsg );
}