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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '177fd9d56b3abdb7cfea4be0428ac81c4ca3adbfcf039c3f64aa2e8bb7a28de2' 
  AND token = 'E2KaRftyJrkTC72Lg3lV2Ix/LUB8YiL2V1oBnK9W1gQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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