Special character handling in Model Driven MES
- Last UpdatedFeb 06, 2026
- 1 minute read
Unsupported special characters in Model Driven MES can cause failures or unexpected behavior when used in MES object names, SQL filtering, Web API requests, or Middleware Access URIs. These characters are interpreted as SQL wildcard/control symbols, are not escaped by Work Tasks when forming API calls, or result in invalid URIs. The following table summarizes unsupported characters in Model Driven MES by area of use:
|
Area of use |
Disallowed characters |
Notes |
|
MES object names and IDs |
% (percent) _ (underscore) ^ (carat) [ ] (square brackets) |
These special characters can cause unexpected behavior when retrieving records because SQL Server LIKE treats them as wildcard/control characters. |
|
SQL filtering operations |
These special characters are used by SQL Server calls that use the LIKE operator. If the characters are used in SQL filter expressions filter operations may behave unexpectedly or break. |
|
|
Web API calls |
& (ampersand) \ (backslash) < (left chevron) " (double quotation) |
These special characters are not escaped when Work Tasks forms make Web API calls, causing API errors. |
|
Middleware access URI usage |
These special characters return errors unless escaped in URIs or calls. |
In general, avoid using these special characters in all MES object identifiers, Work Tasks inputs, Web API payloads, and any data involved in SQL filtering or Middleware access operations.