What is the main difference between a UNION statement and a UNION ALL statement? 1. A UNION statement eliminates duplicate rows; a UNION ALL statement includes duplicate rows. 2. A UNION statement can be used to combine any number of queries; a UNION ALL statement can be used to combine a maximum of two queries. 3. A UNION statement can only combine queries that have parallel fields in the SELECT list; a UNION ALL statement can combine queries with differing SELECT list structures. 4. A UNION statement cannot be used with aggregate functions; a UNION ALL statement can be used with aggregate functions. 5. There is no difference between the two statements; they are interchangeable.
2 76761 SELECT a.field1, b.field2, c.field3, d.field4 2 FROM atable a, atable b, ctable c, dtable d 3 ? 4 ORDER BY 1 What is the minimum number of joins that must be specified on line 3 in the sample code above to properly link the tables? Notice that the table "atable" is aliased twice: once as "a" and once as "b." 1. One join 2. Two joins 3. Three joins 4. Four joins 5. Five joins
6 8531SELECT flavor, SUM (ice_cream_sales) FROM sales_detail GROUP BY flavor ORDER BY 2 DESC If the "sales_detail" table contains ten records with different values in the flavor column (two "vanilla," three "chocolate," four "strawberry," and one NULL), how many rows are returned by the sample code above? 1. 0 rows 2. 1 row 3. 3 rows 4. 4 rows 5. 10 rows
8 10102Which one of the following is a reason that an INSERT statement might cause an error instead of executing correctly? 1. The INSERT statement was attempting to insert a record into a view that was created from more than one table. 2. The INSERT statement was attempting to insert a record using a combination of constants and values from an existing table. 3. The INSERT statement was attempting to insert a record with a non-NULL value into a table that has that column defined as NULL. 4. The INSERT statement was attempting to insert a record into a table by selecting a record from that same table. 5. The INSERT statement was attempting to insert a record into a view rather than a table.
1 5853How to retrieve a second highest salary from a table? Note:Suppose salaries are in duplicate values eg: Name Sal Malli 60000 Pandi 60000 Rudra 45000 Ravi 45000
10 13194Post New Sonata SQL PLSQL Interview Questions
Explain what is the meaning of ctr and how you can calculate?
What is the history of apache mahout? When did it start?
Explain snp horizon.
How do i startup with Remedy testing tool. Couldnot able to find any links for startup. Please help me to startup with this remedy tool.
How do you undo ctrl t in word?
What are components in cakephp.
what is the basic steps for designing an ups,inverters, and battery connections for series and parrallel connections in ups
Can we autowire an interface?
What is the integral value of 1/((ax+b)pow(-8))?
Are methods and constructors the same thing?
before transformer oil dielectric strenght tests are taken the oil should be allowed to settle to remove option 1 air bubbles 2 gasses 3 contamination 4 water
What are the different views in UML?
Is xhtml still used 2018?
What are NBFCs?
What is the domain testing?