SELECT 
  feature_id, 
  variant_id, 
  value, 
  value_int 
FROM 
  cscart_product_features_values 
WHERE 
  product_id = 8877 
  AND lang_code = 'de'

Query time 0.00063

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_product_features_values ref lang_code,product_id,product_id_idx,product_feature_idx product_id 3 const 123 Using where

Result

feature_id variant_id value value_int
23 103
23 101
19 5989 0.600
30 240
42 145
22 98
75 243
21 96
24 107
127 5895
128 5899
129 5902
178 6308
20 6059 1.000
134 5962
152 6118
152 6107
152 6116
152 6106
152 6105
152 6102
152 6101
152 6114
152 6100
152 6097
149 0 5702326178351
152 6096
152 6095
152 6094
152 6093
152 6092
152 6090
152 6089