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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a157b2b5a464685ea988b4e6b30cbfdd83f79c7737d1828c295b4fda48e69754' 
  AND token = 'WhXL7L5yqFwM0sV0c/BcQ+hE2SEW9FLWx1lD9Ov56ZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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