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Question
______ command is used to remove the primary key from a table in SQL.
Options
update
remove
alter
drop
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Solution
Alter command is used to remove the primary key from a table in SQL.
Explanation:
The alter table command is used to remove the primary key from a table in SQL.
Syntax to remove the primary key:
ALTER TABLE table_name DROP PRIMARY KEY;
So, the correct answer is Alter.
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RELATED QUESTIONS
Each table comprises of ______ and ______.
Case Based
Consider the table STUDENT with the following detail.
| STU_ID | NAME | STREAM | MARKS | CLASS |
| 1. | Aditya | Science | 87.5 | 12A |
| 2. | Vikram | Commerce | 88.7 | 12B |
| 3. | Astha | Humanities | 76.8 | 12C |
| 4. | Varsha | Science | 79.5 | 12A |
| 5. | Kanishka | Science | 77.9 | 12A |
| 6. | Anand | Commerce | 86.7 | 12B |
Now answer the question given below:
Command to select all Science students from the table STUDENT
Case Based
Consider the table STUDENT with the following detail.
| STU_ID | NAME | STREAM | MARKS | CLASS |
| 1. | Aditya | Science | 87.5 | 12A |
| 2. | Vikram | Commerce | 88.7 | 12B |
| 3. | Astha | Humanities | 76.8 | 12C |
| 4. | Varsha | Science | 79.5 | 12A |
| 5. | Kanishka | Science | 77.9 | 12A |
| 6. | Anand | Commerce | 86.7 | 12B |
Now answer the question given below:
Delete records that belongs to 'Humanities' stream.
Which of the following command is used to remove a relation from an SQL database?
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- RollNo - integer
- Name - string
- Clas - integer
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Statement 2 - to execute the query that extracts records of those students whose marks are greater than 75.
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import mysql.connector as mysql
def sql_data():
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_________________________ #Statement 2
data=__________________ #Statement 3
for i in data:
print(i)
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| 101 | KARAN | 366 | 410 | 402 | I |
| 102 | NAMAN | 300 | 350 | 325 | I |
| 103 | ISHA | 400 | 410 | 415 | I |
| 104 | RENU | 350 | 357 | 415 | I |
| 105 | ARPIT | 100 | 75 | 178 | IV |
| 106 | SABINA | 100 | 205 | 217 | II |
| 107 | NEELAM | 470 | 450 | 471 | I |
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| Table: Personal | ||||
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| P01 | Rohit | Manager | 89000 | 4800 |
| P02 | Kashish | Clerk | NULL | 1600 |
| P03 | Mahesh | Superviser | 48000 | NULL |
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| P05 | Ravina | Superviser | NULL | 2100 |
Based on the given table, write SQL queries for the following:
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