Reading diagnostics

Every problem SQLQuack reports is a coded diagnostic, underlined in the source as rustc does:

error[SQ0004]: a name does not resolve
 --> query.sql:1:15
  |
1 | SELECT a FROM orders
  |               ^^^^^^ relation `ORDERS` has no known columns
  |
  = help: declare the relation and its columns in the schema (`--schema` on the command line)

The first line has the code and the message. The arrow gives the file, line and column. The caret line underlines the exact span and carries a label for this occurrence. = note: and = help: lines follow when the code has them.

Two kinds of problem

Kind	Codes	What to do
The SQL is not valid Snowflake	SQ0001, SQ01xx, SQ02xx	Fix the SQL. sqlquack check finds these without a schema.
Valid SQL that can’t be translated safely	SQ0002 to SQ0008	Declare the schema, change the policy, or rewrite the construct.

sqlquack check reports only the first kind. sqlquack convert reports both: a statement that does not parse, or that Snowflake rejects, is refused before conversion is tried.

JSON output

With --json, each diagnostic is an object:

{
  "severity": "error",
  "code": "SQ0203",
  "name": "qualify_without_window",
  "alias": null,
  "message": "QUALIFY needs a window function",
  "span": { "start": 9, "end": 16, "line": 1, "column": 10, "end_line": 1, "end_column": 17 },
  "label": "QUALIFY is used without a window function in the SELECT list or QUALIFY",
  "notes": [],
  "help": "move the condition to WHERE or HAVING, or filter on a window function's result"
}

Field	Meaning
code	SQ and four digits. Never reused or renumbered.
name	The code’s stable name, such as unresolved_name.
alias	A parser guard’s former E_GUARD_* name, or null.
message	The code’s title, sometimes with the construct.
span	Character start and end, then one-based line, column, end_line and end_column. Absent only for problems outside the SQL, such as session parameters.
label	What is wrong at this span.
notes, help	Context, and what to change.

Every code is listed in the diagnostic reference. To read one in the terminal, by code or by name:

sqlquack explain SQ0203
sqlquack explain qualify_without_window

It prints the code’s title, explanation, help and an example that draws it, and exits 2 for an unknown code.