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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fe6c74c9fbbf4a19d87be401cbc805effe8dcc954a934f5968c486b068c6fcd7' 
  AND token = 'zTg3b5QfY5F6FwLXDbLPgpm4+Y2qhiS5yoVC/TAE3I8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}