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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5120d0b76d70900bbe51cbf4ea85e7944d9450b4e7aefd5b56e1a9500386a729' 
  AND token = 'RrcEQ2kOeQCmFK/TBwAnY4MU5/+1TzQ/V3SQfXoYwL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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