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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f78f991e4e3c486ba6566f77a8957d513e5ecf2d0dd0e640bdb030b0b5ad38c' 
  AND token = 'c5gmIJtCtOsnISgWHitaCCI8DfQchEdhIrJ0UM6iIlI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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