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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '918ed85929f052e3ed568736e24390cb948b29fa5ced67be6da1ba392a664ca1' 
  AND token = 'TToBXF2fK4eb2lLumJnBo0wEE44JMSyzNR8GXOfhueM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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