Return the DuckDB SQL expression that reconstructs a plain-text abstract from the abstract_inverted_index column in OpenAlex works data.

The expression walks the map, collects (position, word) pairs, sorts by position ascending, and joins words with single spaces. Returns NULL when abstract_inverted_index is NULL.

Usage

oa_works_abstract_sql()

Value

A character scalar containing the SQL expression.

Details

abstract_inverted_index is normalised to MAP(VARCHAR, BIGINT[]) via a double JSON cast (::JSON::MAP(VARCHAR, BIGINT[])) before map_entries() is called. This makes the expression safe regardless of whether DuckDB inferred the column as MAP, STRUCT, or VARCHAR (raw JSON text): all three round-trip through the JSON representation identically.