Errors validating tables with special characters in identifiers

[nj1973]

I am documenting issues discovered while working on issue #1192 that are unrelated to the original issue I was fixing.

Working on this issue is blocked by #1192 because the test tables/tests mentioned below are to be delivered as part of that issue.

Oracle
Test test_row_validation_identifiers is skipped because it fails with:

WITH t0 AS
*
ERROR at line 1:
ORA-04054: database link AT does not exist

This is because the concat__all expression does not quote column names:

...
, t2."RSTRIP__IFNULL__CAST__COL-HYPHEN" AS "RSTRIP__IFNULL__CAST__COL-HYPHEN"
, t2."RSTRIP__IFNULL__CAST__COL@AT" AS "RSTRIP__IFNULL__CAST__COL@AT"
, t2.rstrip__ifnull__cast__other_data AS rstrip__ifnull__cast__other_data
, rstrip__ifnull__cast__id || rstrip__ifnull__cast__col#hash || rstrip__ifnull__cast__col$dollar || rstrip__ifnull__cast__col-hyphen || rstrip__ifnull__cast__col@at || rstrip__ifnull__cast__other_data AS concat__all
FROM t2) t3
...

BigQuery
Tests test_column_validation_identifiers and test_row_validation_identifiers are skipped because they fail with:

google.api_core.exceptions.BadRequest: 400 Name length__col#hash not found inside t1 at [7:17]

Teradata
All three test_*_validation_identifiers tests fail with:

E           pandas.errors.DatabaseError: Execution failed on sql '
E               HELP COLUMN udf.dvt-identifier$_#.*;
E               ': [Version 20.0.0.12] [Session 3718] [Teradata Database] [Error 3807] Object 'udf' does not exist.