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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5755ea6e8cf05682034f88395d36893cc1c1d8a78afc3f6747bd1d983e55550' 
  AND token = 'jtc5ph+DvqQ5vUSOOHB4m1mh8vGSWtaQVM8d3TQ0B3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}