0

と という名前の 2 つの MySQL テーブルがstockinありstockoutます。ここで、serialno という名前の一意の列の 2 つのテーブルをチェックして、在庫のある行を見つけたいと思います。2 つのテーブル間でランダムにルックアップするために、4 つのクエリ行を選択してみました。しかし、実行に時間がかかりすぎるすべてのクエリ。間違った問題がないか、テーブルのテーブル インデックスを確認できますか? 修正や提案があれば、よろしくお願いします。

mysql> SHOW INDEX FROM stockin\G
*************************** 1. row ***************************
        Table: stockin
   Non_unique: 0
     Key_name: PRIMARY
 Seq_in_index: 1
  Column_name: stockin_id
    Collation: A
  Cardinality: 14657
     Sub_part: NULL
       Packed: NULL
         Null:
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 2. row ***************************
        Table: stockin
   Non_unique: 1
     Key_name: shiptype
 Seq_in_index: 1
  Column_name: shiptype
    Collation: A
  Cardinality: 18
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 3. row ***************************
        Table: stockin
   Non_unique: 1
     Key_name: userid
 Seq_in_index: 1
  Column_name: userid
    Collation: A
  Cardinality: 22
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 4. row ***************************
        Table: stockin
   Non_unique: 1
     Key_name: uom
 Seq_in_index: 1
  Column_name: uom
    Collation: A
  Cardinality: 10
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 5. row ***************************
        Table: stockin
   Non_unique: 1
     Key_name: warehouseid
 Seq_in_index: 1
  Column_name: warehouse_id
    Collation: A
  Cardinality: 6
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 6. row ***************************
        Table: stockin
   Non_unique: 1
     Key_name: project_id_for_stockin
 Seq_in_index: 1
  Column_name: project_id
    Collation: A
  Cardinality: 2
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 7. row ***************************
        Table: stockin
   Non_unique: 1
     Key_name: cus_id
 Seq_in_index: 1
  Column_name: cus_id
    Collation: A
  Cardinality: 2
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
7 rows in set (0.01 sec)

と

mysql> SHOW INDEX FROM stockout\G
*************************** 1. row ***************************
        Table: stockout
   Non_unique: 0
     Key_name: PRIMARY
 Seq_in_index: 1
  Column_name: stockout_id
    Collation: A
  Cardinality: 19654
     Sub_part: NULL
       Packed: NULL
         Null:
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 2. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: eng_id
 Seq_in_index: 1
  Column_name: eng_id
    Collation: A
  Cardinality: 5
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 3. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: project_id
 Seq_in_index: 1
  Column_name: project_id
    Collation: A
  Cardinality: 9
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 4. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: warehouseid
 Seq_in_index: 1
  Column_name: warehouseid
    Collation: A
  Cardinality: 47
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 5. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: response_type_id
 Seq_in_index: 1
  Column_name: response_type_id
    Collation: A
  Cardinality: 5
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 6. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: cus_id
 Seq_in_index: 1
  Column_name: cus_id
    Collation: A
  Cardinality: 1
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 7. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: employee_id
 Seq_in_index: 1
  Column_name: employee_id
    Collation: A
  Cardinality: 19
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 8. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: userid
 Seq_in_index: 1
  Column_name: userid
    Collation: A
  Cardinality: 1
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
*************************** 9. row ***************************
        Table: stockout
   Non_unique: 1
     Key_name: uom
 Seq_in_index: 1
  Column_name: uom
    Collation: A
  Cardinality: 11
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
9 rows in set (0.02 sec)

ありがとう

4

1 に答える 1

0

2 つのテーブル間のランダム ルックアップを解決して、一意の列がランダム チェックされているインデックスを追加しました。次のコードのように、すぐにインデックスに列を追加しました。結果の実行時間に驚きました。そのクエリには 3.30 分以上かかっていましたが、インデックスを追加すると0.03数秒しかかかりませんでした。

CREATE INDEX columnname ON tablename(columnname)
于 2013-06-06T09:58:52.140 に答える