How to configure indexes in PostgreSQL to ensure fast search across all keys in a table?

To ensure fast search across all keys in a PostgreSQL table, indexes are usually created on the columns that are expected to be searched. If you need to search by multiple keys simultaneously, you can use several separate indexes or a composite index.

However, if full-text search or search across multiple columns is required, consider:

• GIN indexes using the tsvector data type for full-text search.
• GIN indexes on JSONB for quick search by keys and values in JSON.
• Composite indexes for frequently used column combinations.

Example of creating a full-text index:

ALTER TABLE documents ADD COLUMN tsv tsvector;
UPDATE documents SET tsv = to_tsvector('english', coalesce(title,'') || ' ' || coalesce(body,''));
CREATE INDEX idx_tsv ON documents USING GIN(tsv);

To automatically update the tsvector, a trigger can be used.

If the search is across all keys in JSONB, then the index:

CREATE INDEX idx_jsonb_gin ON table_name USING GIN (jsonb_column);

In conclusion, index setup depends on the data type and query nature. It is important to analyze query execution plans (EXPLAIN) and create indexes that truly speed up the necessary operations.