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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f6b6f22ec2c63132c6b9e5f7d5f5e8df4be1f1f4c43ec1d0979b2e0725f3d303' 
  AND token = 'JB4uW7UZ6KyZYRRuHxAHDZerL1KmGM/yHBagb1/EoNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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