Introduction to SQL What operator tests column for the absence of data? None of these IS NULL operator EXISTS operator NOT operator None of these IS NULL operator EXISTS operator NOT operator ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL Which of the following query finds the name of the sailors who have reserved at least two boats? All of these SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid <> r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid ≠ r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND COUNT(r1.bid) > r2.bid All of these SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid <> r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND r1.sid = r2.sid AND r1.bid ≠ r2.bid SELECT DISTINCT s.sname FROM sailors s, reserves r1, reserves r2 WHERE s.sid = r1.sid AND COUNT(r1.bid) > r2.bid ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL A dynamic view is one whose contents materialize when referenced. True False True False ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL To define what columns should be displayed in an SQL SELECT statement: use SELECT to name the source table(s) and list the columns to be shown after USING. use USING to name the source table(s) and list the columns to be shown after SELECT. use USING to name the source table(s) and list the columns to be shown after WHER use FROM to name the source table(s) and list the columns to be shown after SELECT. use SELECT to name the source table(s) and list the columns to be shown after USING. use USING to name the source table(s) and list the columns to be shown after SELECT. use USING to name the source table(s) and list the columns to be shown after WHER use FROM to name the source table(s) and list the columns to be shown after SELECT. ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL Which command undo all the updates performed by the SQL in the transaction? TRUNCATE ROLLBACK COMMIT DELETE TRUNCATE ROLLBACK COMMIT DELETE ANSWER DOWNLOAD EXAMIANS APP
Introduction to SQL SQL query and modification commands make up a(n) ________ . DML HTML XML DDL DML HTML XML DDL ANSWER DOWNLOAD EXAMIANS APP