concat method
Concat this string db value with other
,
other
may be StringField or String
Implementation
StringField concat(dynamic other) {
assert(other is String || other is StringField);
var result = StringField();
result.queryBuilder = () =>
'(${buildQuery()} || ${other is StringField ? other.buildQuery() : '?'})';
result.parametersBuilder = () => getParameters()
..addAll(
[if (other is StringField) ...(other.getParameters()) else other]);
return result;
}