SQL Formatter
Format, Minify And Escape SQL

What An SQL Formatter Does For You

A query you copy from a log or a tool often sits on one long line. You cannot read it, and you cannot review it. So you need to break it into lines, add indents and put each clause in its place.

This tool does that in one box. First, paste your SQL. Then pick Format, and the result appears as you type. It puts SELECT, FROM and WHERE on their own lines, and it lines up joins and conditions.

It also minifies SQL, which is useful when you must paste a query into code or a config file. In addition, it escapes and unescapes text, so a quote inside a value cannot break your statement.

Everything runs in your browser. So your SQL never leaves your device. That matters, because queries often hold table names, ids and sometimes real data.

Format SQL Into Readable Lines

First, the tool reads your text and splits it into tokens. A token is a word, a number, a string, a comment or a symbol. Because it reads strings and comments first, a keyword inside quotes is never changed.

Then it lays the tokens out. Each main clause starts on a new line. The select list gets one column per line when it has more than one. Joins start a new line, and the AND and OR in a condition line up under the WHERE.

Subqueries sit inside brackets and move one level to the right. So you can see where each one starts and ends.

For more detail, see: Wikipedia article on SQL.

Indents, Keywords And Comments

You choose the indent. Two spaces, four spaces and tabs are all there. You also choose the keyword case. Uppercase is the classic style. Lowercase is popular in modern code. A third choice leaves your keywords as you typed them.

Also, comments are safe. A line comment stays at the end of its line, and a block comment stays where you put it. If you prefer a clean result, switch comments off.

So the tool does not change names, values or strings. It only moves white space and changes the case of keywords.

Minify SQL

Then there is minify, which does the reverse. It removes comments and extra white space and keeps one space only where two words would otherwise touch.

That helps when you store a query in a string. It also helps in a URL or a log. The result is the same query, only shorter. The notes under the result show how many characters you saved.

Escape And Unescape SQL Text

A quote inside a value ends a string too early. That is a bug, and it can also be a security hole. So you must escape the quote before you put the text in a statement.

Standard SQL doubles the quote, so it becomes two single quotes. MySQL also accepts a backslash before the quote. The tool does both, and it can add the outer quotes for you.

Then unescape goes the other way. It removes the outer quotes and turns each doubled quote or backslash sequence back into plain text.

Escaping Is Not A Full Defence

Escaping helps for one off text, such as a value in a script. For an app, use prepared statements with parameters instead. They keep data and code apart, so no quote can change the query.

The formatter leaves parameters such as a colon name or a question mark alone. So a prepared statement stays valid after you format it.

Which SQL Does It Understand

First, the tool works with the common core of SQL. That covers SELECT, INSERT, UPDATE, DELETE, WITH and CREATE TABLE, plus joins, unions, window functions and CASE.

Also, it reads strings in single quotes, names in double quotes, backticks and square brackets, and both kinds of comments. So it suits MySQL, PostgreSQL, SQL Server, SQLite and Oracle code.

Some engine specific syntax may look plain, but it still stays valid. The tool never rewrites a statement, so it cannot break it.

Stored procedures and long scripts work too. The tool treats each semicolon as the end of a statement, so a script with many statements stays in order.

Safe By Design

The tool never runs your SQL and never connects to a database. It only reads text and writes text, and it does so in your tab.