Question

A(n) ____ in a SQL command instructs Oracle 12c to use a substituted value in place of the variable at the time the command is actually executed.​

A) Placeholder
B) Index
C) Alias
D) Constant

Answer 1

The correct answer to the question is A) Placeholder, which is used in Oracle 12c SQL commands to indicate that a substituted value should be used when the command is executed.

Step-by-step explanation:

In a SQL command within Oracle 12c, a placeholder is used to instruct the database management system to substitute the placeholder with an actual value at the time the command is executed. The correct answer to the question is A) Placeholder. Placeholders are also commonly referred to as bind variables in Oracle, and they are typically denoted by a leading colon (e.g., :variable_name) in SQL statements.

Placeholders are useful for writing more efficient and secure SQL code. By using placeholders, you can avoid SQL injection attacks and allow the database to create more optimized execution plans.