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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2bb14a7b3f258312e0b77a820781d2b7a84787c8df5dc13d7b3b9b4c9544d47' 
  AND token = 'lvhwLdDfIYT1WWAeQ+ZE3AMDW7ND2c/FH8u+JHV1x4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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