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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86bbf4489ace53b436583b19f6348c75148cbd8650bdbf0010c1d93d3ae0af53' 
  AND token = 'J0r2lWkKSd3W/4ZutHk6NQE99Lmh7NR3LxMGAAba59c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

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