Uppercase SQL Keywords

Why uppercase keywords

For decades the dominant SQL style has been uppercase reserved words — SELECT, FROM, WHERE, JOIN, GROUP BY — set against lowercase or mixed-case identifiers. The reason is purely visual: SQL has no indentation rules of its own, so casing becomes the main way to separate the language's machinery from your data's names. When keywords shout in uppercase, the skeleton of the query is instantly recognisable, and a column that happens to be named order or select is easy to tell apart from the keyword.

Not everyone agrees, and that is fine. Some modern style guides prefer all-lowercase SQL for a calmer look. The important thing is consistency within a codebase, and a one-click converter makes whichever convention you choose effortless to apply.

Keywords change, identifiers do not

The crucial detail is that case conversion must be selective. You want select to become SELECT, but you absolutely do not want userId to become USERID — in case-sensitive databases that would break the query, and even where it works it destroys readable camelCase names. This tool only recases tokens it recognises as reserved words and data types. Everything else is left byte-for-byte as written.

select firstName, lastName from Users where isActive = 1

becomes:

SELECT
  firstName,
  lastName
FROM
  Users
WHERE
  isActive = 1

Notice firstName, Users and isActive are untouched — only the keywords were promoted to uppercase.

Three casing modes

Data types follow the same rule, so varchar becomes VARCHAR in uppercase mode. Pick the mode that matches your house style and the whole query is converted in one pass.

Apply it to legacy code

Inherited SQL is rarely consistent — one developer typed keywords in caps, another in lowercase, a third mixed both in the same statement. Running the converter over those queries gives the whole file a single voice in seconds, which makes the next round of edits far easier to read. Because the conversion runs locally in your browser, you can normalise even proprietary queries without uploading them anywhere, and the page keeps working with no connection at all.