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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a49603e91002564c8331f505c8728c8efdf0ae6ae5a5bf2e6faf9b205f5d268a' 
  AND token = 'D12Uf3Nqe2vOAhmnc5gMsFYl57ibM//0Qfv/itAIj9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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