Cursors for row iteration in MySQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a cursor named 'cur' for selecting all rows from the 'employees' table.

MySQL

DECLARE [1] CURSOR FOR SELECT * FROM employees;

Drag options to blanks, or click blank then click option'

Acursor

Bcur1

Ccur

Dmycursor

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'cursor' as the cursor name which is a keyword.

Forgetting to declare the cursor before using it.

The cursor name is declared right after the DECLARE keyword. Here, 'cur' is the cursor name.

2fill in blank

medium

Complete the code to open the cursor named 'cur'.

MySQL

OPEN [1];

Drag options to blanks, or click blank then click option'

Acur

Bcur1

Ccursor

Dmycursor

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to open a cursor with a different name than declared.

Missing the semicolon at the end.

To start fetching rows, you must open the cursor by its declared name, here 'cur'.

3fill in blank

hard

Fix the error in the FETCH statement to retrieve data into the variable 'emp_name'.

MySQL

FETCH [1] INTO emp_name;

Drag options to blanks, or click blank then click option'

Acur

Bcursor

Ccur1

Dmycursor

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong cursor name in FETCH.

Not declaring the variable before FETCH.

The FETCH statement must use the exact cursor name declared and opened, here 'cur'.

4fill in blank

hard

Fill both blanks to declare a handler for NOT FOUND condition and close the cursor named 'cur'.

MySQL

DECLARE CONTINUE HANDLER FOR [1] SET done = TRUE;
CLOSE [2];

Drag options to blanks, or click blank then click option'

ANOT FOUND

BSQLSTATE '02000'

Ccur

Ddone

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong condition name in handler.

Closing a cursor with a wrong name.

The handler must catch the 'NOT FOUND' condition, and the cursor to close is 'cur'.

5fill in blank

hard

Fill all three blanks to fetch rows from cursor 'cur', check for done, and leave the loop if done.

MySQL

FETCH [1] INTO emp_name;
IF [2] THEN
  LEAVE [3];
END IF;

Drag options to blanks, or click blank then click option'

Acur

Bdone

Cloop_label

Demp_name

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong cursor name in FETCH.

Checking wrong variable for done condition.

Leaving a loop with wrong label.

FETCH uses cursor 'cur', the done flag is checked, and the loop labeled 'loop_label' is exited.