Q170
Will the following SQL command produce any error? INSERT INTO person (person_id, fname,lname) VALUES (1,’S’,’U’), VALUES (2,’T’,’U’); /* where person_id is a primary key */
A.
Error
B.
No Error
AnswerC.
Depends
D.
None of the mentioned
Answer: Option B
Solution
Answer: Option B
Solution:
This question is about understanding how MySQL handles INSERT statements with multiple VALUES clauses.
Let's break down the code:
* INSERT INTO person (person_id, fname, lname): This part tells MySQL we want to add data into the "person" table, specifically to the columns "person_id", "fname", and "lname".
* VALUES (1, 'S', 'U'), VALUES (2, 'T', 'U');: This is where the problem lies. We're trying to insert two rows of data at once, but the syntax is incorrect. In MySQL, you can't use multiple VALUES clauses within a single INSERT statement.
Therefore, the correct answer is Option A: Error.
Why is this an error?
MySQL expects only one set of values to be provided with each INSERT statement. The second VALUES clause would be interpreted as a separate, invalid statement.
How to fix it?
To insert multiple rows correctly, use a single VALUES clause with multiple sets of values separated by commas:
```sql INSERT INTO person (person_id, fname, lname) VALUES (1, 'S', 'U'), (2, 'T', 'U'); ```
This will insert both rows of data correctly.
Remember: Understanding the correct syntax for SQL statements is crucial for avoiding errors and ensuring your data is handled properly.