Why PostgreSQL has rich data types - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to select all columns from the table named 'employees'.

PostgreSQL

SELECT [1] FROM employees;

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A*

Ball

Ccolumns

Deverything

Attempts:

3 left

💡 Hint

Common Mistakes

Using words like 'all' or 'columns' instead of the symbol *.

Forgetting to specify what to select.

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

2fill in blank

medium

Complete the code to create a table named 'products' with a column 'price' that stores decimal numbers.

PostgreSQL

CREATE TABLE products (price [1]);

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ABOOLEAN

BVARCHAR

CDECIMAL

DTEXT

Attempts:

3 left

💡 Hint

Common Mistakes

Using VARCHAR or TEXT which store text, not numbers.

Using BOOLEAN which stores true/false values.

DECIMAL is used to store numbers with decimal points, perfect for prices.

3fill in blank

hard

Fix the error in the code to create a table with a column 'created_at' that stores date and time.

PostgreSQL

CREATE TABLE orders (created_at [1]);

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ATIME

BDATE

CDATETIME

DTIMESTAMP

Attempts:

3 left

💡 Hint

Common Mistakes

Using DATE which stores only the date without time.

Using TIME which stores only the time without date.

Using DATETIME which is not a PostgreSQL data type.

TIMESTAMP stores both date and time, which is needed for 'created_at'.

4fill in blank

hard

Fill both blanks to create a table 'locations' with a column 'coordinates' that stores geometric points.

PostgreSQL

CREATE TABLE locations (coordinates [1]); -- Use [2] for geometric data type

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APOINT

BVARCHAR

CINTEGER

DBOOLEAN

Attempts:

3 left

💡 Hint

Common Mistakes

Using VARCHAR or INTEGER which are not geometric types.

Using BOOLEAN which stores true/false values.

POINT is the PostgreSQL data type for geometric points, used for coordinates.

5fill in blank

hard

Fill all three blanks to create a table 'users' with a JSON column 'profile', a UUID column 'user_id', and a boolean column 'active'.

PostgreSQL

CREATE TABLE users (user_id [1], profile [2], active [3]);

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

AJSON

BUUID

CBOOLEAN

DTEXT

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up data types like using TEXT instead of JSON.

Using VARCHAR for UUID or BOOLEAN columns.

UUID is used for unique identifiers, JSON stores structured data, and BOOLEAN stores true/false values.