SELECT ts_headline(content, to_tsquery('english', 'search')) FROM documents;
But get an error: function ts_headline(text, tsquery) does not exist. What is the likely cause?
AThe <code>ts_headline</code> function requires a text query string, not tsquery
BThe <code>ts_headline</code> function does not accept <code>to_tsquery</code> results directly
CThe <code>ts_headline</code> function requires three arguments including language
DThe <code>to_tsquery</code> function is used incorrectly without casting
Step-by-Step Solution
Solution:
Step 1: Check function signature
ts_headline accepts text and tsquery but sometimes requires explicit casting or correct argument types.
Step 2: Identify error cause
The error suggests no matching function for ts_headline(text, tsquery). This often happens if to_tsquery is used without proper casting or language config mismatch.
Final Answer:
The to_tsquery function is used incorrectly without casting -> Option D
Quick Check:
Incorrect to_tsquery usage = B [OK]
Quick Trick:Cast to_tsquery output properly for ts_headline [OK]
Common Mistakes:
Assuming ts_headline accepts any tsquery without casting
Forgetting to match language configs
Confusing argument order or types
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