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I inherited some some bad SQL code (zero documentation and I'm missing the original requirements). In the where clause, it has the following:

A OR B AND C AND D OR E

From my knowledge of logical operands, my assumption is that SQL would compile this as:

A OR (B AND C AND D) OR E

Is that correct?

I have a feeling the intent was 

(A OR B) AND C AND (D OR E)

and I will need to speak with those that requested this project in the first place, as I haven't seen the original requirements.

user3654225
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    Your understanding of boolean operator precedence is exactly right: AND is stronger than OR, exactly like multiplication is vs. addition. Your guess as to the intent is probably also 100% correct (meaning that the condition is written incorrectly) but you won't know without asking those who requested the project. –  Aug 22 '18 at 18:07
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    If you are going to add parentheses, then the correct version would be: `(A OR ((B AND C) AND D)) OR E`. This is semantically equivalent to your second version. – Gordon Linoff Aug 22 '18 at 18:08
  • [Documentation for condition precedence](https://docs.oracle.com/en/database/oracle/oracle-database/12.2/sqlrf/About-SQL-Conditions.html#GUID-65B103FE-C00C-46A3-8173-A731DBF62C80), showing that you are right as `AND` has higher precedence than `OR`. – Alex Poole Aug 22 '18 at 18:42
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    @GordonLinoff - No, the version you propose is not equivalent to the OP's second version. And it is impossible to know what the "correct" version is, without knowing the intent (the requirement). –  Aug 22 '18 at 18:53

1 Answers1

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You are correct. In the absence of parenthesis this should be interpreted as:

A OR (B AND C AND D) OR E
The Impaler
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