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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2cde7ee9ee0ee6ad18c6232396d4a84c7bdb06707a7bd96a673b3f81a363471' 
  AND token = 'ZsXSbcvgvvx8twvjfAYx+Jtmj0DAvDNy/VV0Z3+yT7c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}