[FORMATTING] Parse error when there are Column with Number Prefix

[duwanqiebi]

Input data

Which SQL and options did you provide as input?

select 34_dffdfd from table_name

Expected Output

  select 34_dffdfd
     from table_name

Actual Output

An Unexpected Error Occurred
Parse error: Unexpected "34_dffdfd " at line 1 column 8. SQL dialect used: "spark".

Please report this at [Github issues page.](https://github.com/sql-formatter-org/sql-formatter/issues)

Stack Trace:

Error: Parse error: Unexpected "34_dffdfd " at line 1 column 8.
SQL dialect used: "spark".
    at T.default.createParseError (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:233790)
    at T.default.tokenize (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:233556)
    at T.default.tokenize (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:228858)
    at T.default.tokenize (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:243624)
    at T.default.reset (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:242151)
    at T.O.feed (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:268202)
    at Object.parse (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:243762)
    at T.default.parse (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:16428)
    at T.default.format (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:16326)
    at T.formatDialect (https://unpkg.com/sql-formatter@latest/dist/sql-formatter.min.js:1:26

Usage

• How are you calling / using the library? yes
• What SQL language(s) does this apply to? Spark
• Which SQL Formatter version are you using? 15.6

[nene]

Thanks for reporting.

Perhaps you could tell me what is the syntax allowed for identifiers in Spark SQL. The official docs are unclear about the exact syntax.

[duwanqiebi]

From the documentation, column names support numbers, but there is no restriction against starting a name with a number

This is a real SQL query in my case.

[nene]

Question: Is the comma also part of identifier name?

I don't think it is, but from the documentation it seems like it might be.

[nene]

I guess the actual syntax is like this:

• identifier can contain letters (a-z, A-Z), numbers (0-9) and underscore (_).
• identifiers must contain at least one letter or underscore.

Like 42_ would be a valid identifier, but just 42 would be a number. Right?

[nene]

I added support for starting identifiers with a digit.

Additional question: Can an identifier also contain unicode letters? Like would õlu be a valid identifier?

[duwanqiebi]

I guess the actual syntax is like this:

• identifier can contain letters (a-z, A-Z), numbers (0-9) and underscore (_).
• identifiers must contain at least one letter or underscore.

Like 42_ would be a valid identifier, but just 42 would be a number. Right?

Yes. That's correct

[duwanqiebi]

I added support for starting identifiers with a digit.

Additional question: Can an identifier also contain unicode letters? Like would õlu be a valid identifier?

I have tried in spark. It does not support unicode letters.

[duwanqiebi]

Question: Is the comma also part of identifier name?

I don't think it is, but from the documentation it seems like it might be.

I don't think spark supprot comma as identifier name too.

[nene]

OK. Great. I've released the fix in 15.6.1.