/**
* Returns true if a type is a simple cast of another type. It is if the cast type is nullable and
* the cast is one of the following:
* <li>x TO x
* <li>char(n) TO varchar(m)
* <li>varchar(n) TO varchar(m)
* <li>x not null TO x nullable
*
* @param origType original type passed into the cast operand
* @param castType type the operand will be casted to
* @return true if the cast is simple
*/
private boolean isCastSimple(RelDataType origType, RelDataType castType) {
SqlTypeName origTypeName = origType.getSqlTypeName();
SqlTypeName castTypeName = castType.getSqlTypeName();
if (!(castType.isNullable())) {
return false;
}
Charset origCharset = origType.getCharset();
Charset castCharset = castType.getCharset();
if ((origCharset != null) || (castCharset != null)) {
if ((origCharset == null) || (castCharset == null)) {
return false;
}
if (!origCharset.equals(castCharset)) {
return false;
}
}
return ((origType == castType)
|| ((origTypeName == SqlTypeName.CHAR) && (castTypeName == SqlTypeName.VARCHAR))
|| ((origTypeName == SqlTypeName.VARCHAR) && (castTypeName == SqlTypeName.VARCHAR))
|| ((origTypeName == castTypeName)
&& (origType.getPrecision() == castType.getPrecision())
&& ((origTypeName != SqlTypeName.DECIMAL)
|| (origType.getScale() == castType.getScale()))
&& (!origType.isNullable() && castType.isNullable())));
}
public static void checkCharsetAndCollateConsistentIfCharType(RelDataType type) {
// (every charset must have a default collation)
if (SqlTypeUtil.inCharFamily(type)) {
Charset strCharset = type.getCharset();
Charset colCharset = type.getCollation().getCharset();
assert null != strCharset;
assert null != colCharset;
if (!strCharset.equals(colCharset)) {
if (false) {
// todo: enable this checking when we have a charset to
// collation mapping
throw new Error(
type.toString()
+ " was found to have charset '"
+ strCharset.name()
+ "' and a mismatched collation charset '"
+ colCharset.name()
+ "'");
}
}
}
}
