to_tsquery for search terms in PostgreSQL - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ query_result

intermediate

Basic to_tsquery search output

Given a table documents with a text column content, what rows will match the query to_tsquery('cat & dog')?

PostgreSQL

SELECT id, content FROM documents WHERE to_tsvector(content) @@ to_tsquery('cat & dog');

A Rows where content contains 'cat' followed immediately by 'dog' with no words between

B Rows where content contains either 'cat' or 'dog', but not necessarily both

C Rows where content contains the exact phrase 'cat dog' in sequence

D Rows where content contains both 'cat' and 'dog' anywhere in the text

💡 Hint

The & operator means AND in to_tsquery syntax.

The & operator in to_tsquery means both terms must be present anywhere in the text. So only rows containing both 'cat' and 'dog' match.

❓ query_result

intermediate

Using OR operator in to_tsquery

What is the result of this query?
SELECT id FROM documents WHERE to_tsvector(content) @@ to_tsquery('cat | dog');

A Rows containing either 'cat' or 'dog' or both

B Rows containing both 'cat' and 'dog' only

C Rows containing the exact phrase 'cat dog'

D Rows containing neither 'cat' nor 'dog'

💡 Hint

The | operator means OR in to_tsquery syntax.

The | operator means either term can be present. So rows with 'cat', 'dog', or both will match.

📝 Syntax

advanced

Identify the syntax error in to_tsquery

Which option contains a syntax error when used inside to_tsquery()?

A 'cat & | dog'

B 'cat | dog'

C 'cat & dog'

D 'cat <-> dog'

💡 Hint

Check operator placement and usage rules.

The & and | operators cannot be adjacent without a term between them. Option A has '& |' which is invalid syntax.

❓ query_result

advanced

Phrase search with <-> operator

What does this query return?
SELECT id FROM documents WHERE to_tsvector(content) @@ to_tsquery('cat <-> dog');

A Rows where 'cat' and 'dog' appear separated by exactly one word

B Rows where 'cat' is immediately followed by 'dog' in the text

C Rows where 'cat' or 'dog' appear anywhere in the text

D Rows where 'cat' and 'dog' appear anywhere in the text, order doesn't matter

💡 Hint

The <-> operator means words are adjacent in order.

The <-> operator matches phrases where the first word is immediately followed by the second word.

🧠 Conceptual

expert

Understanding lexeme normalization in to_tsquery

Which statement about to_tsquery lexeme normalization is true?

A It ignores stop words but does not stem words

B It searches for exact word matches without any normalization

C It converts words to their root form (stemming) before searching

D It only matches words at the start of the text

💡 Hint

Think about how PostgreSQL handles word variations in full text search.

to_tsquery applies stemming to convert words to their root forms, so searches match different word forms.