DO blocks for anonymous code in PostgreSQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start a DO block in PostgreSQL.

PostgreSQL

DO [1] $$ BEGIN RAISE NOTICE 'Hello, world!'; END; $$;

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

ALANGUAGE javascript

BLANGUAGE sql

CLANGUAGE python

DLANGUAGE plpgsql

Attempts:

3 left

💡 Hint

Common Mistakes

Using a language not supported by PostgreSQL DO blocks.

Omitting the LANGUAGE keyword.

The DO block in PostgreSQL requires specifying the language, usually plpgsql for procedural code.

2fill in blank

medium

Complete the code to declare a variable inside a DO block.

PostgreSQL

DO LANGUAGE plpgsql $$ DECLARE my_var [1]; BEGIN my_var := 10; RAISE NOTICE 'Value: %', my_var; END; $$;

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Ainteger

Bdate

Cboolean

Dtext

Attempts:

3 left

💡 Hint

Common Mistakes

Using a text type for a numeric value.

Not declaring the variable type.

Variables in PL/pgSQL must have a type. Here, my_var is an integer.

3fill in blank

hard

Fix the error in the DO block by completing the missing keyword.

PostgreSQL

DO LANGUAGE plpgsql $$ [1] my_var integer := 5; BEGIN RAISE NOTICE 'Value: %', my_var; END; $$;

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ADECLARE

BSET

CDEFINE

DCREATE

Attempts:

3 left

💡 Hint

Common Mistakes

Using SET or CREATE instead of DECLARE.

Placing variable declarations inside BEGIN without DECLARE.

In PL/pgSQL DO blocks, variables must be declared in a DECLARE section before the BEGIN block.

4fill in blank

hard

Fill the blank to complete the DO block that loops from 1 to 3 and raises a notice.

PostgreSQL

DO LANGUAGE plpgsql $$ DECLARE i [1]; BEGIN FOR i IN 1..3 LOOP RAISE NOTICE 'Number: %', i; END LOOP; END; $$;

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

Atext

Bboolean

Cinteger

Ddate

Attempts:

3 left

💡 Hint

Common Mistakes

Using text or boolean types for loop counters.

Not declaring the variable before BEGIN.

The variable i is declared as an integer and used in the FOR loop.

5fill in blank

hard

Fill all three blanks to complete a DO block that declares a variable, assigns a value, and raises a notice.

PostgreSQL

DO LANGUAGE plpgsql $$ DECLARE my_var [1]; BEGIN my_var := [2]; RAISE NOTICE 'Value is %', [3]; END; $$;

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

Ainteger

B20

Cmy_var

Dtext

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning a string to an integer variable.

Printing a value instead of the variable.

The variable my_var is declared as integer, assigned 20, and printed.