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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd8d3afa7cd7c045ee9b09f8630eff1bc22a7e1c0c61445f51f074cc0a52f787' 
  AND token = 'RpSDCo1dNcnqm25Fh19IRpIFaP/LDktN4bfRfQWfE/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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