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To combine multiple retrievals, we write several SELECT statements and put the keyword between them. What is the keyword?

To combine multiple retrievals, we write several SELECT statements and put the keyword between them. What is the keyword? Correct Answer UNION

The ‘UNION’ operator is used for combining the results of various ‘SELECT’ queries into one. For example, ‘SELECT a FROM table1 UNION SELECT a FROM table2;’ produces the results from tables table1 concatenated with that of table2.

Related Questions

To combine multiple retrievals, which keyword is used to write several SELECT statements between them?
Consider the following partial Schedule S involving two transactions T1 and T2. Only the read and the write operations have been shown. The read operation on data item P is denoted by read(P) and the write operation on data item P is denoted by write(P) Time Instance Transaction-id T1 T2 1 read(A)   2 write(A)   3   read(C) 4   write(C) 5   read(B) 6   write(B) 7   read(A) 8   Commit 9 read(B)     Schedule S   Suppose that the transaction T1 fails immediately after time instance 9. Which one of the following statements is correct?
S1: Always remember that regular and frequent practice is essential if you are to learn to write well.
P: Even with the most famous writers, inspiration is rare.
Q: Writing is 99 percent hard work and one percent inspiration, so the sooner you get into the habit of writing, the better.
R: It is no good waiting until you have an inspiration before you write.
S: You learn to write by writing.
S6: If you keep your eyes and ears open, you will find plenty of things to write about around you to be able to discipline yourself to write.

The Proper sequence should be:
Rohan put 9 cards on a table, some face up and the rest face down. How many were put face down? A. Rohan put an even number of the cards face up. B. Rohan put twice as many of the cards face up as he put face down. Select the correct answer from the options given below:
Some small cubes of same height 7 cm but variable length and width are put inside a large cuboid of height 21 cm. Length and width of cuboid is 32 cm and 24 cm, respectively. Small cubes are put such that cubes at the bottom most layer is of similar base area; second layer contains all the cubes of similar base area and third layer have all the cubes of similar base area. Which of the following statement(s) given below is / are TRUE? A: If side of each small cubes at bottom most layer is 8 cm, then maximum number of small cubes that can be put at bottom most layer is 12. B: If maximum of 48 cubes can be put at second layer, then side of each cube at second layer is 6 cm. C: If side of each small cubes at third layer is 1.6 cm, then maximum number of small cubes that can be put at third layer is 300.
There are 5 players of P, Q, R, S, and T. Each of them live on different floors of the five-storey building, which are named as the ground floor, first floor, second floor, third floor and fourth floor. Each of them prefers different sports, such as shot put, javelin throw, kabaddi, long jump and gymnastics but not necessarily in the same order. (i) S likes long jump and lives just below T,who lives on the third floor. (ii) Two players live in between R and Q, R and Q prefer spear throw and shot put respectively. (iii) The player who likes gymnastics lives on the ground floor and lives just below the player who likes the shot put. Who lives on the middle floor of the floors on which T and Q live?
Assume a two-level inclusive cache hierarchy, L1 and L2, where L2 is the larger of the two. Consider the following statements. S1: Read misses in a write through L1 cache do not result in writebacks of dirty lines to the L2. S2: Write allocate policy must be used in conjunction with write through caches and no-write allocate policy is used with writeback caches. Which of the following statements is correct? 
Fact 1: Some pens don't write.
Fact 2: All blue pens write.
Fact 3: Some writing utensils are pens.

If the first three statements are facts, which of the following statements must also be a fact?
I: Some writing utensils don't write.
II: Some writing utensils are blue.
III: Some blue writing utensils don't write.
Each of the following problem has a question and two statements which are labeled 1. and. Use the data given in 1. and 2. to decide whether the statements are sufficient to answer the question.Select one of the following . a.Statements (1) ALONE is sufficient,but (2) ALONE is not sufficient. b.Statements (2) ALONE is sufficient,but (1) ALONE is not sufficient. c. Both statement TOGETHER are sufficient but statement alone is sufficient . Is K a multiple of 6? (1)K is a multiple of 3. (2) K is a multiple of 12.
Consider a Simple Checkpointing Protocol and the following set of operations in the log. (start, T4); (write, T4, y, 2, 3); (start, T1); (commit, T4); (write, T1, z, 5, 7); (Checkpoint); (start, T2); (write, T2, x, 1, 9); (commit, T2); start, T3); (write, T3, z, 7, 2); if a crash happens now and the system tries to recover using both undo and redo operations, what are the contents of the undo list and the redo list?