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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '258e1d368592f39108161816fcb8985d2103040563710b311b28d6d7ba211f54' 
  AND token = '6xt4LYYsEB9Tlyj11QVsfzXPwsW1cAi3AOE2+01xQoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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