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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b029cb2c9d6bc2fafd73e9da4a554ceed4372af20391033e6a2eb56d1b4b5a0d' 
  AND token = 'gznBdeegJTpWQv83Vx5YmqQ3tzbPW6if+CWzIplEXS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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