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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '994e9bfee1c3227db934fa1e38b6735711900cc6e9bdbd57c0ba35557c44f463' 
  AND token = '4WZISNcHfW4Gt82sacc0oA4EdT6kANHb93qoFQ081tQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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