Feedback collection and annotation in LangChain - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to select all feedback entries from the feedback table.

LangChain

SELECT [1] FROM feedback;

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

Auser_id

Bid

Ccomment

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using a specific column name when all columns are needed.

Leaving the SELECT clause empty.

The asterisk (*) selects all columns from the table.

2fill in blank

medium

Complete the code to insert a new feedback comment into the feedback table.

LangChain

INSERT INTO feedback (user_id, comment) VALUES ([1], 'Great service!');

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

A'user123'

B123

C'Great service!'

Duser_id

Attempts:

3 left

💡 Hint

Common Mistakes

Using quotes around numeric values.

Inserting the comment text in place of user_id.

The user_id is usually a number, so 123 is correct here.

3fill in blank

hard

Fix the error in the query to update a feedback comment by id.

LangChain

UPDATE feedback SET comment = 'Updated comment' WHERE id = [1];

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

A1

B'abc'

C'1'

Dcomment

Attempts:

3 left

💡 Hint

Common Mistakes

Putting numeric id inside quotes.

Using a string value that does not exist.

The id is numeric, so it should not be in quotes.

4fill in blank

hard

Fill both blanks to select feedback comments with rating greater than 3.

LangChain

SELECT comment FROM feedback WHERE rating [1] [2];

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

A>

B3

C<

Drating

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of >.

Comparing rating to a column name instead of a number.

The condition rating > 3 selects feedback with rating higher than 3.

5fill in blank

hard

Fill all three blanks to create a dictionary of user_id to comment for feedback with rating above 4.

LangChain

SELECT [1], [2] FROM feedback WHERE rating [3] 4;

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

Auser_id

Bcomment

C>

Drating

Attempts:

3 left

💡 Hint

Common Mistakes

Selecting wrong columns.

Using incorrect comparison operator.

Select user_id and comment where rating is greater than 4.

Practice

1. What is the main purpose of feedback collection in a database?

easy

A. To speed up database queries

B. To delete old user data automatically

C. To store user opinions for later review

D. To create user accounts

Solution

1. Step 1: Understand feedback collection

   Feedback collection means saving what users say or think about something.

2. Step 2: Identify the purpose in database context

   In databases, feedback is stored so it can be reviewed or analyzed later.

3. Final Answer:

   To store user opinions for later review -> Option C

4. Quick Check:

   Feedback collection = store opinions [OK]

Hint: Feedback stores user opinions, not deletes or speeds queries [OK]

Common Mistakes:

• Confusing feedback with user account data
• Thinking feedback speeds up queries
• Assuming feedback deletes old data

2. Which SQL command correctly creates a table named feedback with columns id (integer) and comment (text)?

easy

A. CREATE feedback TABLE (id INT, comment TEXT);

B. CREATE TABLE feedback (id INT, comment TEXT);

C. MAKE TABLE feedback (id INTEGER, comment STRING);

D. TABLE CREATE feedback (id INT, comment TEXT);

Solution

1. Step 1: Recall correct SQL syntax for table creation

   The correct syntax starts with CREATE TABLE, followed by table name and columns with types.

2. Step 2: Check each option for syntax correctness

   CREATE TABLE feedback (id INT, comment TEXT); uses correct keywords and types. Others have wrong keywords or order.

3. Final Answer:

   CREATE TABLE feedback (id INT, comment TEXT); -> Option B

4. Quick Check:

   CREATE TABLE + columns = CREATE TABLE feedback (id INT, comment TEXT); [OK]

Hint: CREATE TABLE is the right start for making tables [OK]

Common Mistakes:

• Using MAKE TABLE instead of CREATE TABLE
• Wrong order of keywords
• Using STRING instead of TEXT for text columns

3. Given the table feedback with columns id and comment, what will this query return?

SELECT comment FROM feedback WHERE id = 2;

medium

A. Only the comment text where id equals 2

B. An error because id is not selected

C. All ids and comments

D. All comments with id 2

Solution

1. Step 1: Understand the SELECT statement

   The query asks for the comment column only, filtering rows where id equals 2.

2. Step 2: Determine what is returned

   Only the comment text for the row with id 2 is returned, not all comments or ids.

3. Final Answer:

   Only the comment text where id equals 2 -> Option A

4. Quick Check:

   SELECT comment WHERE id=2 = Only the comment text where id equals 2 [OK]

Hint: SELECT column filters output columns, WHERE filters rows [OK]

Common Mistakes:

• Thinking all comments with id 2 means multiple rows
• Expecting id column in output when not selected
• Assuming syntax error due to missing id in SELECT

4. Identify the error in this SQL statement for inserting feedback:

INSERT INTO feedback (id, comment) VALUES 1, 'Great service';

medium

A. Missing parentheses around VALUES

B. Wrong table name

C. Missing semicolon

D. Using single quotes instead of double quotes

Solution

1. Step 1: Review correct INSERT syntax

   VALUES must be followed by parentheses enclosing the values to insert.

2. Step 2: Check the given statement

   The statement lacks parentheses around 1, 'Great service' after VALUES.

3. Final Answer:

   Missing parentheses around VALUES -> Option A

4. Quick Check:

   VALUES requires parentheses [OK]

Hint: Always put parentheses around VALUES in INSERT [OK]

Common Mistakes:

• Forgetting parentheses after VALUES
• Confusing quotes for strings
• Assuming semicolon is mandatory for error

5. You want to label feedback comments as 'positive' or 'negative' in a new column annotation. Which SQL command correctly adds this column to the feedback table?

hard

A. INSERT COLUMN annotation INTO feedback;

B. UPDATE feedback ADD annotation TEXT;

C. CREATE COLUMN annotation TEXT IN feedback;

D. ALTER TABLE feedback ADD COLUMN annotation TEXT;

Solution

1. Step 1: Understand how to add a new column

   To add a column, use ALTER TABLE with ADD COLUMN and specify the type.

2. Step 2: Check each option's correctness

   ALTER TABLE feedback ADD COLUMN annotation TEXT; uses correct syntax. Others use invalid commands or order.

3. Final Answer:

   ALTER TABLE feedback ADD COLUMN annotation TEXT; -> Option D

4. Quick Check:

   ALTER TABLE + ADD COLUMN = ALTER TABLE feedback ADD COLUMN annotation TEXT; [OK]

Hint: Use ALTER TABLE ADD COLUMN to add new columns [OK]

Common Mistakes:

• Using UPDATE instead of ALTER TABLE
• Trying to CREATE COLUMN separately
• Using INSERT COLUMN which is invalid