A strange operation problem in SQL Server: -100/-100*10 = 0

Understanding the pecking order: SQL Operative Precedence

Operator precedence essentially boils down to a pecking order — it dictates how mathematical operations are interpreted in SQL Server. Multiplication (*) and division (/) sit higher on the totem pole than unary negation (-).

Unary and Binary: An equation of balance:

One of the key aspects to remember is the preeminence of binary over unary operations in SQL Server.

• Unary negation (-) ranks lower than multiplication (*) and division (/).
• Parentheses are essential when you are trying to enforce predictability in operation order with potential discrepancies caused by unary negation.
• Complex operations without parentheses could spin a web of confusion leading to unexpected outcomes.

Busting the left-to-right myth

While operators of the same precedence level are evaluated left-to-right, the unary operation adds a twist. It removes the simplicity of left-to-right computation leading to unexpected results.

Minus the Negation:

Within an operation like -100/-100*10, division should be prioritized, followed by multiplication. But, due to the esoteric behavior of unary negation in SQL Server, the outcome strays off this beaten path.

Why parentheses are a SQL developer's best friend

Parentheses are essential for ensuring accurate and precise calculations in SQL. They work on two levels — firstly, boosting the clarity of your query, and secondly, they help in safeguarding the integrity of your data, essentially serving as a trusted companion to any SQL professional.

-- This operation, like a well-balanced meal, is full of parentheses, ensuring portions (calculations) are served (calculated) just right!
SELECT (-100 / -100) * 10 AS Result;  -- Returns 10
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Peeking beyond the operation

While trying to deep dive into SQL Server arithmetic operations, it's important to consider multiple factors that might be all the difference between an incorrect and the perfect result.

Getting the right input:

Any operation is only as good as its input — ensure to consider data type precedence and the effects of type casting in your mathematical operations.

The enigma named SQL arithmetic:

The world of SQL Server arithmetic is full of surprises — equip yourself with the knowledge of unique SQL Server behaviors and rules.

Real-world application:

The above points are not just theoretical — they hold immense practical implications. From financial computations to scientific data processing, maintaining unequivocal precision is non-negotiable.