long start = file.getFilePointer();
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
int bufferLen = 0;
for (Value[] row : rows) {
buff.reset();
buff.writeInt(0);
for (int j = 0; j < columnCount; j++) {
Value v = row[j];
buff.checkCapacity(buff.getValueLen(v));
buff.writeValue(v);
}