public RelNode convertSqlToRel(String sql) {
Util.pre(sql != null, "sql != null");
final SqlNode sqlQuery;
try {
sqlQuery = parseQuery(sql);
} catch (Exception e) {
throw Util.newInternal(e); // todo: better handling
}
final RelDataTypeFactory typeFactory = getTypeFactory();
final Prepare.CatalogReader catalogReader = createCatalogReader(typeFactory);
final SqlValidator validator = createValidator(catalogReader, typeFactory);
final SqlToRelConverter converter =
createSqlToRelConverter(validator, catalogReader, typeFactory);
converter.setTrimUnusedFields(true);
final SqlNode validatedQuery = validator.validate(sqlQuery);
final RelNode rel = converter.convertQuery(validatedQuery, false, true);
Util.post(rel != null, "return != null");
return rel;
}
/**
* Validates this node in an expression context.
*
* <p>Usually, this method does much the same as {@link #validate}, but a {@link SqlIdentifier}
* can occur in expression and non-expression contexts.
*/
public void validateExpr(SqlValidator validator, SqlValidatorScope scope) {
validate(validator, scope);
Util.discard(validator.deriveType(scope, this));
}