Informatica SQL 4, 5

• Informatiemanagement
• WO
• Studiejaar 4

SQL - 4

UPDATE

4) UPDATE

The UPDATE statement is used to modify the existing records in a table.

UPDATE [Table Name]

SET [Column Name]=['Value 1'], [Column Name2=['Value2']

WHERE [Column Name]='   '

StudentsTable

UPDATE StudentsTable

SET Lesson='Math'

WHERE StudentID= '613109'

StudentsTable

Chris decided that his favourite lesson was actually Chemistry. What should we type in order to update his favourite lesson?

1. UPDATE StudentsTable SET Lesson='Chemistry' WHERE StudentID='Chris'
2. UPDATE StudentsTable SET Lesson='Chemistry' WHERE StudentID='983376'
3. UPDATE StudentsTable SET Lesson='Chemistry' WHERE Name='Chris'
4. UPDATE StudentsTable SET Lesson='Chemistry' WHERE column1='983376'

JOINs

The JOIN statement is used to combine rows from two or more tables, based on a related column between them.

• INNER JOIN
• LEFT JOIN
• RIGHT JOIN
• FULL JOIN