Query Fails Validation

Start with the diagnostic code, then narrow the problem by validation layer: syntax, parameters, dialect, or schema.

Fast Triage

• Check Errors, Warnings, and ErrorSummary first.
• If the code is QL0001, focus on structural SQL or dialect syntax.
• If the code is QL0030 or QL0031, focus on validation parameters.
• If the code references tables, columns, procedures, or write restrictions, confirm that Level 3 is active and the schema snapshot is current.

Helpful Jumps

• Error Codes
• Supported Validation Rules
• Validation Results and Diagnostics

Example

var query = new SqlQuery("SELECT FROM customers");

Assert.False(query.IsValid);
Assert.Equal("QL0001", query.Errors[0].Code);
Assert.NotEmpty(query.ErrorSummary);