docs: private boolean checkIfColumnTypeChangeIsSupported(VoltType oldType, int oldSize,
                                                         VoltType newType, int newSize,
                                                         boolean oldInBytes, boolean newInBytes)
      {
          // increases in size are cool; shrinks not so much
          if (oldType == newType) {
              if (oldType == VoltType.STRING && oldInBytes == false && newInBytes == true) {
                  // varchar CHARACTER to varchar BYTES
                  return oldSize * 4 <= newSize;
              }
              return oldSize <= newSize;
          }
  
          // allow people to convert timestamps to longs
          // (this is useful if they accidentally put millis instead of micros in there)
          if ((oldType == VoltType.TIMESTAMP) && (newType == VoltType.BIGINT)) {
              return true;
          }
  
          // allow integer size increase and allow promotion to DECIMAL
          if (oldType == VoltType.BIGINT) {
              if (newType == VoltType.DECIMAL) {
                  return true;
              }
          }
          // also allow lossless conversion to double from ints < mantissa size
          else if (oldType == VoltType.INTEGER) {
              if ((newType == VoltType.DECIMAL) ||
                  (newType == VoltType.FLOAT) ||
                  newType == VoltType.BIGINT) {
                  return true;
              }
          }
          else if (oldType == VoltType.SMALLINT) {
              if ((newType == VoltType.DECIMAL) ||
                  (newType == VoltType.FLOAT) ||
                  (newType == VoltType.BIGINT) ||
                  (newType == VoltType.INTEGER)) {
                  return true;
              }
          }
          else if (oldType == VoltType.TINYINT) {
              if ((newType == VoltType.DECIMAL) ||
                  (newType == VoltType.FLOAT) ||
                  (newType == VoltType.BIGINT) ||
                  (newType == VoltType.INTEGER) ||
                  (newType == VoltType.SMALLINT)) {
                  return true;
              }
          }
          return false;
      }