void Table::serializeTo(SerializeOutput &serialOutput) {
// The table is serialized as:
// [(int) total size]
// [(int) header size] [num columns] [column types] [column names]
// [(int) num tuples] [tuple data]
/* NOTE:
VoltDBEngine uses a binary template to create tables of single integers.
It's called m_templateSingleLongTable and if you are seeing a serialization
bug in tables of single integers, make sure that's correct.
*/
// a placeholder for the total table size
std::size_t pos = serialOutput.position();
serialOutput.writeInt(-1);
serializeColumnHeaderTo(serialOutput);
// active tuple counts
serialOutput.writeInt(static_cast<int32_t>(m_tupleCount));
int64_t written_count = 0;
TableIterator titer = iterator();
TableTuple tuple(m_schema);
while (titer.next(tuple)) {
tuple.serializeTo(serialOutput);
++written_count;
}
assert(written_count == m_tupleCount);
// length prefix is non-inclusive
int32_t sz = static_cast<int32_t>(serialOutput.position() - pos - sizeof(int32_t));
assert(sz > 0);
serialOutput.writeIntAt(pos, sz);
}
void Table::serializeColumnHeaderTo(SerializeOutput &serialOutput) {
/* NOTE:
VoltDBEngine uses a binary template to create tables of single integers.
It's called m_templateSingleLongTable and if you are seeing a serialization
bug in tables of single integers, make sure that's correct.
*/
// skip header position
std::size_t start;
// use a cache
if (m_columnHeaderData) {
assert(m_columnHeaderSize != -1);
serialOutput.writeBytes(m_columnHeaderData, m_columnHeaderSize);
return;
}
assert(m_columnHeaderSize == -1);
start = serialOutput.position();
// skip header position
serialOutput.writeInt(-1);
//status code
serialOutput.writeByte(-128);
// column counts as a short
serialOutput.writeShort(static_cast<int16_t>(m_columnCount));
// write an array of column types as bytes
for (int i = 0; i < m_columnCount; ++i) {
ValueType type = m_schema->columnType(i);
serialOutput.writeByte(static_cast<int8_t>(type));
}
// write the array of column names as voltdb strings
// NOTE: strings are ASCII only in metadata (UTF-8 in table storage)
for (int i = 0; i < m_columnCount; ++i) {
// column name: write (offset, length) for column definition, and string to string table
const string& name = columnName(i);
// column names can't be null, so length must be >= 0
int32_t length = static_cast<int32_t>(name.size());
assert(length >= 0);
// this is standard string serialization for voltdb
serialOutput.writeInt(length);
serialOutput.writeBytes(name.data(), length);
}
// write the header size which is a non-inclusive int
size_t position = serialOutput.position();
m_columnHeaderSize = static_cast<int32_t>(position - start);
int32_t nonInclusiveHeaderSize = static_cast<int32_t>(m_columnHeaderSize - sizeof(int32_t));
serialOutput.writeIntAt(start, nonInclusiveHeaderSize);
// cache the results
m_columnHeaderData = new char[m_columnHeaderSize];
memcpy(m_columnHeaderData, static_cast<const char*>(serialOutput.data()) + start, m_columnHeaderSize);
}
bool Table::serializeTo(int32_t offset, int32_t limit, SerializeOutput &serialize_io) {
// The table is serialized as:
// [(int) total size]
// [(int) header size] [num columns] [column types] [column names]
// [(int) num tuples] [tuple data]
/* NOTE:
VoltDBEngine uses a binary template to create tables of single integers.
It's called m_templateSingleLongTable and if you are seeing a serialization
bug in tables of single integers, make sure that's correct.
*/
// a placeholder for the total table size
std::size_t pos = serialize_io.position();
serialize_io.writeInt(-1);
if (!serializeColumnHeaderTo(serialize_io))
return false;
// active tuple counts
uint32_t output_size = m_tupleCount;
if (limit != -1 || offset != -1) {
if (offset == -1) {
output_size = (limit < m_tupleCount ? limit : m_tupleCount);
} else if (offset > m_tupleCount) {
output_size = 0;
} else {
output_size = m_tupleCount - offset;
if (limit != -1 && limit < output_size) output_size = limit;
}
}
serialize_io.writeInt(static_cast<int32_t>(output_size));
// fprintf(stderr, "SERIALIZE(output=%d, offset=%d, limit=%d, total=%d)\n", output_size, offset, limit, m_tupleCount);
int64_t written_count = 0;
int64_t read_count = 0;
TableIterator titer(this);
TableTuple tuple(m_schema);
while (titer.next(tuple)) {
if (offset == -1 || read_count >= offset) {
tuple.serializeTo(serialize_io);
if (limit != -1 && ++written_count == limit) break;
}
read_count++;
}
// assert(written_count == m_tupleCount);
// length prefix is non-inclusive
int32_t sz = static_cast<int32_t>(serialize_io.position() - pos - sizeof(int32_t));
assert(sz > 0);
serialize_io.writeIntAt(pos, sz);
return true;
}
/**
* Serialized the table, but only includes the tuples specified (columns data and all).
* Used by the exception stuff Ariel put in.
*/
void Table::serializeTupleTo(SerializeOutput &serialOutput, voltdb::TableTuple *tuples, int numTuples) {
//assert(m_schema->equals(tuples[0].getSchema()));
std::size_t pos = serialOutput.position();
serialOutput.writeInt(-1);
assert(!tuples[0].isNullTuple());
serializeColumnHeaderTo(serialOutput);
serialOutput.writeInt(static_cast<int32_t>(numTuples));
for (int ii = 0; ii < numTuples; ii++) {
tuples[ii].serializeTo(serialOutput);
}
serialOutput.writeIntAt(pos, static_cast<int32_t>(serialOutput.position() - pos - sizeof(int32_t)));
}