QSql*Model: add SQL syntax helper

Change-Id: Ia53e30d7a2f2bb5b4f76c32fcf0fe526d1e4ab51
Reviewed-by: Honglei Zhang <honglei.zhang@nokia.com>

1 files changed, 27 insertions, 36 deletions

diff --git a/src/sql/models/qsqltablemodel.cpp b/src/sql/models/qsqltablemodel.cpp
index 0e5eba1a73..20d2be36e1 100644
--- a/src/sql/models/qsqltablemodel.cpp
+++ b/src/sql/models/qsqltablemodel.cpp
@@ -55,6 +55,8 @@
 
 QT_BEGIN_NAMESPACE
 
+typedef QSqlTableModelSql Sql;
+
 /*! \internal
     Populates our record with values.
 */
@@ -411,8 +413,9 @@ bool QSqlTableModel::selectRow(int row)
                                               d->tableName,
                                               d->primaryValues(row),
                                               false);
-    if (d->filter.startsWith(QLatin1String("WHERE "), Qt::CaseInsensitive))
-        d->filter.remove(0, 6);
+    static const QString wh = Sql::where() + Sql::sp();
+    if (d->filter.startsWith(wh, Qt::CaseInsensitive))
+        d->filter.remove(0, wh.length());
     const QString stmt = selectStatement();
     d->sortColumn = table_sort_col;
     d->filter = table_filter;
@@ -589,8 +592,8 @@ bool QSqlTableModel::updateRowInTable(int row, const QSqlRecord &values)
 
     const QSqlRecord whereValues = d->primaryValues(row);
     const bool prepStatement = d->db.driver()->hasFeature(QSqlDriver::PreparedQueries);
-    QString stmt = d->db.driver()->sqlStatement(QSqlDriver::UpdateStatement, d->tableName,
-                                                rec, prepStatement);
+    const QString stmt = d->db.driver()->sqlStatement(QSqlDriver::UpdateStatement, d->tableName,
+                                                     rec, prepStatement);
     const QString where = d->db.driver()->sqlStatement(QSqlDriver::WhereStatement, d->tableName,
                                                        whereValues, prepStatement);
 
@@ -599,9 +602,8 @@ bool QSqlTableModel::updateRowInTable(int row, const QSqlRecord &values)
                                  QSqlError::StatementError);
         return false;
     }
-    stmt.append(QLatin1Char(' ')).append(where);
 
-    return d->exec(stmt, prepStatement, rec, whereValues);
+    return d->exec(Sql::concat(stmt, where), prepStatement, rec, whereValues);
 }
 
 
@@ -656,10 +658,10 @@ bool QSqlTableModel::deleteRowFromTable(int row)
 
     const QSqlRecord whereValues = d->primaryValues(row);
     const bool prepStatement = d->db.driver()->hasFeature(QSqlDriver::PreparedQueries);
-    QString stmt = d->db.driver()->sqlStatement(QSqlDriver::DeleteStatement,
-                                                d->tableName,
-                                                QSqlRecord(),
-                                                prepStatement);
+    const QString stmt = d->db.driver()->sqlStatement(QSqlDriver::DeleteStatement,
+                                                      d->tableName,
+                                                      QSqlRecord(),
+                                                      prepStatement);
     const QString where = d->db.driver()->sqlStatement(QSqlDriver::WhereStatement,
                                                        d->tableName,
                                                        whereValues,
@@ -670,9 +672,8 @@ bool QSqlTableModel::deleteRowFromTable(int row)
                              QSqlError::StatementError);
         return false;
     }
-    stmt.append(QLatin1Char(' ')).append(where);
 
-    return d->exec(stmt, prepStatement, QSqlRecord() /* no new values */, whereValues);
+    return d->exec(Sql::concat(stmt, where), prepStatement, QSqlRecord() /* no new values */, whereValues);
 }
 
 /*!
@@ -923,19 +924,16 @@ void QSqlTableModel::setSort(int column, Qt::SortOrder order)
 QString QSqlTableModel::orderByClause() const
 {
     Q_D(const QSqlTableModel);
-    QString s;
     QSqlField f = d->rec.field(d->sortColumn);
     if (!f.isValid())
-        return s;
-        
-    QString table = d->tableName;
+        return QString();
+
     //we can safely escape the field because it would have been obtained from the database
     //and have the correct case
     QString field = d->db.driver()->escapeIdentifier(f.name(), QSqlDriver::FieldName);
-    s.append(QLatin1String("ORDER BY ")).append(table).append(QLatin1Char('.')).append(field);
-    s += d->sortOrder == Qt::AscendingOrder ? QLatin1String(" ASC") : QLatin1String(" DESC");
-
-    return s;
+    field.prepend(QLatin1Char('.')).prepend(d->tableName);
+    field = d->sortOrder == Qt::AscendingOrder ? Sql::asc(field) : Sql::desc(field);
+    return Sql::orderBy(field);
 }
 
 /*!
@@ -958,34 +956,27 @@ int QSqlTableModel::fieldIndex(const QString &fieldName) const
 QString QSqlTableModel::selectStatement() const
 {
     Q_D(const QSqlTableModel);
-    QString query;
     if (d->tableName.isEmpty()) {
         d->error = QSqlError(QLatin1String("No table name given"), QString(),
                              QSqlError::StatementError);
-        return query;
+        return QString();
     }
     if (d->rec.isEmpty()) {
         d->error = QSqlError(QLatin1String("Unable to find table ") + d->tableName, QString(),
                              QSqlError::StatementError);
-        return query;
+        return QString();
     }
 
-    query = d->db.driver()->sqlStatement(QSqlDriver::SelectStatement,
-                                         d->tableName,
-                                         d->rec,
-                                         false);
-    if (query.isEmpty()) {
+    const QString stmt = d->db.driver()->sqlStatement(QSqlDriver::SelectStatement,
+                                                      d->tableName,
+                                                      d->rec,
+                                                      false);
+    if (stmt.isEmpty()) {
         d->error = QSqlError(QLatin1String("Unable to select fields from table ") + d->tableName,
                              QString(), QSqlError::StatementError);
-        return query;
+        return stmt;
     }
-    if (!d->filter.isEmpty())
-        query.append(QLatin1String(" WHERE ")).append(d->filter);
-    QString orderBy(orderByClause());
-    if (!orderBy.isEmpty())
-        query.append(QLatin1Char(' ')).append(orderBy);
-
-    return query;
+    return Sql::concat(Sql::concat(stmt, Sql::where(d->filter)), orderByClause());
 }
 
 /*!