void RowLoader::process (Task & t)
{
QString sLimitQuery;
if(query.startsWith("PRAGMA", Qt::CaseInsensitive) || query.startsWith("EXPLAIN", Qt::CaseInsensitive))
{
sLimitQuery = query;
} else {
// Remove trailing trailing semicolon
QString queryTemp = rtrimChar(query, ';');
// If the query ends with a LIMIT statement take it as it is, if not append our own LIMIT part for lazy population
if(queryTemp.contains(QRegExp("LIMIT\\s+.+\\s*((,|\\b(OFFSET)\\b)\\s*.+\\s*)?$", Qt::CaseInsensitive)))
sLimitQuery = queryTemp;
else
sLimitQuery = queryTemp + QString(" LIMIT %1, %2;").arg(t.row_begin).arg(t.row_end-t.row_begin);
}
statement_logger(sLimitQuery);
QByteArray utf8Query = sLimitQuery.toUtf8();
sqlite3_stmt *stmt;
int status = sqlite3_prepare_v2(pDb.get(), utf8Query, utf8Query.size(), &stmt, nullptr);
auto row = t.row_begin;
if(SQLITE_OK == status)
{
const int num_columns = headers.size();
while(!t.cancel && sqlite3_step(stmt) == SQLITE_ROW)
{
Cache::value_type rowdata;
for(int i=0;i<num_columns;++i)
{
if(sqlite3_column_type(stmt, i) == SQLITE_NULL)
{
rowdata.append(QByteArray());
} else {
int bytes = sqlite3_column_bytes(stmt, i);
if(bytes)
rowdata.append(QByteArray(static_cast<const char*>(sqlite3_column_blob(stmt, i)), bytes));
else
rowdata.append(QByteArray(""));
}
}
QMutexLocker lk(&cache_mutex);
cache_data.set(row++, std::move(rowdata));
}
}
sqlite3_finalize(stmt);
if(row != t.row_begin)
emit fetched(t.token, t.row_begin, row);
}
int SqliteTableModel::getQueryRowCount()
{
// Return -1 if there is an error
int retval = -1;
// Use a different approach of determining the row count when a EXPLAIN or a PRAGMA statement is used because a COUNT fails on these queries
if(m_sQuery.startsWith("EXPLAIN", Qt::CaseInsensitive) || m_sQuery.startsWith("PRAGMA", Qt::CaseInsensitive))
{
// So just execute the statement as it is and fetch all results counting the rows
sqlite3_stmt* stmt;
QByteArray utf8Query = m_sQuery.toUtf8();
if(sqlite3_prepare_v2(m_db->_db, utf8Query, utf8Query.size(), &stmt, NULL) == SQLITE_OK)
{
retval = 0;
while(sqlite3_step(stmt) == SQLITE_ROW)
retval++;
sqlite3_finalize(stmt);
// Return the results but also set the chunk size the number of rows to prevent the lazy population mechanism to kick in as using LIMIT
// fails on this kind of queries as well
m_chunkSize = retval;
return retval;
}
} else {
// If it is a normal query - hopefully starting with SELECT - just do a COUNT on it and return the results
QString sCountQuery = QString("SELECT COUNT(*) FROM (%1);").arg(rtrimChar(m_sQuery, ';'));
m_db->logSQL(sCountQuery, kLogMsg_App);
QByteArray utf8Query = sCountQuery.toUtf8();
sqlite3_stmt* stmt;
int status = sqlite3_prepare_v2(m_db->_db, utf8Query, utf8Query.size(), &stmt, NULL);
if(status == SQLITE_OK)
{
status = sqlite3_step(stmt);
if(status == SQLITE_ROW)
{
QString sCount = QString::fromUtf8((const char*)sqlite3_column_text(stmt, 0));
retval = sCount.toInt();
}
sqlite3_finalize(stmt);
} else {
qWarning() << "Count query failed: " << sCountQuery;
}
}
return retval;
}
int RowLoader::countRows()
{
int retval = -1;
// Use a different approach of determining the row count when a EXPLAIN or a PRAGMA statement is used because a COUNT fails on these queries
if(query.startsWith("EXPLAIN", Qt::CaseInsensitive) || query.startsWith("PRAGMA", Qt::CaseInsensitive))
{
// So just execute the statement as it is and fetch all results counting the rows
sqlite3_stmt* stmt;
QByteArray utf8Query = query.toUtf8();
if(sqlite3_prepare_v2(pDb.get(), utf8Query, utf8Query.size(), &stmt, nullptr) == SQLITE_OK)
{
retval = 0;
while(sqlite3_step(stmt) == SQLITE_ROW)
retval++;
sqlite3_finalize(stmt);
return retval;
}
} else {
// If it is a normal query - hopefully starting with SELECT - just do a COUNT on it and return the results
QString sCountQuery = QString("SELECT COUNT(*) FROM (%1);").arg(rtrimChar(query, ';'));
statement_logger(sCountQuery);
QByteArray utf8Query = sCountQuery.toUtf8();
sqlite3_stmt* stmt;
int status = sqlite3_prepare_v2(pDb.get(), utf8Query, utf8Query.size(), &stmt, nullptr);
if(status == SQLITE_OK)
{
status = sqlite3_step(stmt);
if(status == SQLITE_ROW)
{
QString sCount = QString::fromUtf8(reinterpret_cast<const char*>(sqlite3_column_text(stmt, 0)));
retval = sCount.toInt();
}
sqlite3_finalize(stmt);
} else {
qWarning() << "Count query failed: " << sCountQuery;
}
}
return retval;
}
void SqliteTableModel::fetchData(unsigned int from, unsigned to)
{
int currentsize = m_data.size();
QString sLimitQuery;
if(m_sQuery.startsWith("PRAGMA", Qt::CaseInsensitive) || m_sQuery.startsWith("EXPLAIN", Qt::CaseInsensitive))
{
sLimitQuery = m_sQuery;
} else {
// Remove trailing trailing semicolon
QString queryTemp = rtrimChar(m_sQuery, ';');
// If the query ends with a LIMIT statement take it as it is, if not append our own LIMIT part for lazy population
if(queryTemp.contains(QRegExp("LIMIT\\s+\\d+\\s*(,\\s*\\d+\\s*)?$", Qt::CaseInsensitive)))
sLimitQuery = queryTemp;
else
sLimitQuery = QString("%1 LIMIT %2, %3;").arg(queryTemp).arg(from).arg(to-from);
}
m_db->logSQL(sLimitQuery, kLogMsg_App);
QByteArray utf8Query = sLimitQuery.toUtf8();
sqlite3_stmt *stmt;
int status = sqlite3_prepare_v2(m_db->_db, utf8Query, utf8Query.size(), &stmt, NULL);
if(SQLITE_OK == status)
{
while(sqlite3_step(stmt) == SQLITE_ROW)
{
QByteArrayList rowdata;
for (int i = 0; i < m_headers.size(); ++i)
rowdata.append(QByteArray(static_cast<const char*>(sqlite3_column_blob(stmt, i)), sqlite3_column_bytes(stmt, i)));
m_data.push_back(rowdata);
}
}
sqlite3_finalize(stmt);
beginInsertRows(QModelIndex(), currentsize, m_data.size()-1);
endInsertRows();
}
