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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fd77f6969d28ba286fd4e8c023780f70eea23b85e8a58485c16bdd5342a9ed4' 
  AND token = 'a8xPlEyAgBJemtnSH5HPtdUWr88PrE/i1CCAGT1w6Rk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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