The SQL Procedure: Trivia Quiz

1. A query that joins a table to itself

Outer join

Self-join

Inner join

A self-join is a type of query where a table is joined with itself. This is done by creating two instances of the same table and then joining them based on a common column. It is often used when there is a need to compare records within the same table. In a self-join, each instance of the table is treated as a separate entity, allowing for comparisons and analysis between the two.

Explanation

A self-join is a type of query where a table is joined with itself. This is done by creating two instances of the same table and then joining them based on a common column. It is often used when there is a need to compare records within the same table. In a self-join, each instance of the table is treated as a separate entity, allowing for comparisons and analysis between the two.

2. An alternative name that you assign to the table in the query’s FROM clause

Query

Table alias

Single-row functions

A table alias is an alternative name that you assign to a table in a query's FROM clause. This allows you to refer to the table using a shorter or more meaningful name within the query. Table aliases are especially useful when you need to join multiple tables in a query, as they help to clarify which table each column belongs to. By using table aliases, you can make your query more concise and easier to read and understand.

Explanation

A table alias is an alternative name that you assign to a table in a query's FROM clause. This allows you to refer to the table using a shorter or more meaningful name within the query. Table aliases are especially useful when you need to join multiple tables in a query, as they help to clarify which table each column belongs to. By using table aliases, you can make your query more concise and easier to read and understand.

3. Removes all of a table’s data without saving any rollback information

Roll Back

Truncate

Single-row functions

Truncate is the correct answer because it removes all of a table's data without saving any rollback information. Unlike the delete statement, which can be rolled back, truncate cannot be undone. It is a faster and more efficient way to remove all data from a table when rollback is not necessary.

Explanation

Truncate is the correct answer because it removes all of a table's data without saving any rollback information. Unlike the delete statement, which can be rolled back, truncate cannot be undone. It is a faster and more efficient way to remove all data from a table when rollback is not necessary.

4. Built-in functions that return a single result for each row of data retrieved

Single-row functions

Search condition

Table alias

Single-row functions are built-in functions that operate on a single row of data at a time and return a single result for each row. These functions can be used to manipulate data values within a query, perform calculations, or apply transformations to the data. Examples of single-row functions include mathematical functions (such as ABS or ROUND), string functions (such as SUBSTR or CONCAT), and date functions (such as TO_CHAR or MONTH). By applying single-row functions to the retrieved data, we can modify or format the values as needed before displaying or using them further.

Explanation

Single-row functions are built-in functions that operate on a single row of data at a time and return a single result for each row. These functions can be used to manipulate data values within a query, perform calculations, or apply transformations to the data. Examples of single-row functions include mathematical functions (such as ABS or ROUND), string functions (such as SUBSTR or CONCAT), and date functions (such as TO_CHAR or MONTH). By applying single-row functions to the retrieved data, we can modify or format the values as needed before displaying or using them further.

5. Contains current date and time

Single-row functions

Savepoint

SYSDATE pseudocolumn

The SYSDATE pseudocolumn is a single-row function that returns the current date and time. It can be used in SQL queries to retrieve the current date and time and perform calculations or comparisons based on it.

Explanation

The SYSDATE pseudocolumn is a single-row function that returns the current date and time. It can be used in SQL queries to retrieve the current date and time and perform calculations or comparisons based on it.

6. A series of action queries that represent a logical unit of work

Query

Single Row Function

Transaction

The correct answer is "Transaction" because a transaction is a series of action queries that represent a logical unit of work. In a transaction, multiple queries are executed together as a single unit, ensuring that either all the queries are successfully executed or none of them are executed. This helps maintain data integrity and consistency in the database.

Explanation

The correct answer is "Transaction" because a transaction is a series of action queries that represent a logical unit of work. In a transaction, multiple queries are executed together as a single unit, ensuring that either all the queries are successfully executed or none of them are executed. This helps maintain data integrity and consistency in the database.