The tables "t1" and "t2" are defined below.
Tables "t1" and "t2" have columns "id" that are of INTEGER type, and columns "name" that are of
TEXT type.
t1
t2
The following SQL command was executed. Select the number of rows in the result. SELECT *
FROM t1 RIGHT OUTER JOIN t2 ON t1.id = t2.id;

• A. 2 rows
• B. 5 rows
• C. 6 rows
• D. 4 rows
• E. 3 rows

What does the following command do? Choose the most appropriate statement from the selection
below.
Note: $ is the command prompt.
$ pg_dump postgres > pgsql

• A. Outputs all of the content of the database postgres to the screen using the user pgsql.
• B. Writes a backup of the database postgres to the file pgsql.
• C. Writes a backup of the entire database cluster using user postgres to the file pgsql.
• D. Backs up the database postgres and writes an error message to the file pgsql.
• E. Writes a backup of the entire database cluster to the file postgres and writes an error message to the file pgsql.

A table is defined as follows:
CREATE TABLE t (id INT, val TEXT);
Select two correct statements from below about the function "get_head" defined below. CREATE
FUNCTION get_head(BOOLEAN)
RETURNS TEXT LANGUAGE sql CALLED ON NULL INPUT
AS 'SELECT val FROM t WHERE $1 OR id > 0 ORDER BY id LIMIT 1;';

• A. Even if this function is passed the same parameter value and executed multiple times, the returned values will not necessarily also be the same value.
• B. If a function with the same name and with type BOOLEAN as the parameter is already defined, an error occurs.
• C. This function is defined using PL/pgSQL.
• D. When NULL is passed for the argument and the function is executed, NULL is returned.
• E. There are cases where this function returns multiple lines.

The present time is noon of July 7th, 2007, and the result of the following
SQL sentence was '2007-07-17 12:00:00'.
Select the correct expression to fill in the blank below.
SELECT CURRENT_TIMESTAMP::timestamp + ________________ ;

• A. '10 day'::interval
• B. 10::day
• C. 8640000::time
• D. age(8640000)
• E. '10 day'::timestamp

Select the correct SQL statement which concatenates strings 'ABC' and 'abc' to form 'ABCabc'.

• A. SELECT 'ABC' || 'abc';
• B. SELECT'ABC' . 'abc';
• C. SELECTcat('ABC', 'abc') FROM pg_operator;
• D. SELECT 'ABC' + 'abc' FROM pg_operator;
• E. SELECT 'ABC' + 'abc';