serialのシーケンスがなが～い名前になる場合の命名ロジック（pg_get_serial_sequenceの中身を想像）

get_serial_sequence.js

var MAX_SEQ_NAME_LENGTH = 63;
var PARTS_LENGTH_THRESHOLD = 29;

function getSerialSequence(tableName, columnName) {
  t = tableName;
  c = columnName;
  if (tableName.length + columnName.length + 5 > MAX_SEQ_NAME_LENGTH) {
    if (tableName.length > PARTS_LENGTH_THRESHOLD) {
      if (columnName.length > PARTS_LENGTH_THRESHOLD) {
        t = tableName.substring(0, PARTS_LENGTH_THRESHOLD);
        c = columnName.substring(0, PARTS_LENGTH_THRESHOLD);
      } else {
        t = tableName.substring(0, PARTS_LENGTH_THRESHOLD + (PARTS_LENGTH_THRESHOLD - columnName.length));
      }
    } else {
        c = columnName.substring(0, PARTS_LENGTH_THRESHOLD + (PARTS_LENGTH_THRESHOLD - tableName.length));
    }
  }
  return t + "_" + c + "_seq";
}