[Data Analysis]A data analyst is evaluating all conditions in a query. Which of the following is the best logical function to accomplish this task?

The AND logical operator is used to combine multiple conditions in a query, such as in a WHERE or HAVING clause. It functions as a logical conjunction, meaning it returns a true result only if all of the individual conditions it connects are true. If any single condition is false, the entire expression evaluates to false. This makes AND the correct choice for ensuring every specified condition is met before a record is included in the result set.

A. OR: The OR operator returns true if any of the connected conditions are met, not necessarily all of them.

B. NOT: The NOT operator is a unary operator used to negate or invert the result of a single condition.

D. IF: The IF function (or CASE statement in SQL) is used for conditional flow control to return different values based on a condition.

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1. Silberschatz

A.

Korth

H. F.

& Sudarshan

S. (2019). Database System Concepts (7th ed.). McGraw-Hill. In Chapter 3

"Introduction to SQL

" Section 3.2.3

"The Where Clause

" the text explains that the AND logical connective allows for the combination of multiple predicates

where the overall predicate is true only if all the combined predicates are true.

2. PostgreSQL 16 Documentation. (2023). Chapter 9: Functions and Operators

Section 9.2: Logical Operators. The official documentation states

"The ordinary logical operators are available: AND

OR

NOT." The truth table provided for AND demonstrates that the result is true only when both boolean inputs are true.

3. Stanford University. (n.d.). CS145: Introduction to Databases

Lecture 2: SQL. Retrieved from https://web.stanford.edu/class/cs145/slides/02-sql1.pdf. Slide 20 ("Conditions in WHERE Clause") explicitly shows the use of AND to combine multiple conditions

stating that the result includes tuples satisfying all specified conditions.