私は基本的な MySQL では「大丈夫」ですが、これは「私の頭の上にある」です!
目的:
- データベースのインポート
- 変更された製品を更新する
- 削除された製品を削除する
- 迅速かつ効率的に
データベーステーブルは巨大で、速度が問題です。
MyISAM は inoDB の方が高速である必要はありませんか? 各データベースは一意のテーブルになります。
私がやろうとしていることの出発点としてこれが与えられました：
CREATE TABLE `table` LIKE LiveTable
LOAD DATA INFILE..... INTO `table`
UPDATE `table` SET delete=1; -- Set the delete field to true because it will not have been updated
UPDATE `table` INNER JOIN`table`ON `LiveTable.ID`=`table.ID`
SET LiveTable.Col1=table.Col1, LiveTable.Col2=table.Col2….. delete=0
INSERT INTO LiveTable(ID,Col1,Col2,… delete=0)
SELECT ID,Col1,Col2,...FROM `table`
LEFT JOIN LiveTable
ON table.ID = LiveTable.ID
WHERE LiveTable.ID IS NULL
DELETE FROM LiveTableWHERE delete = 0
EMPTY TABLE `table`
> CREATE TABLE `product_table` (
> `programname` VARCHAR(100) NOT NULL,
> `name` VARCHAR(160) NOT NULL,
> `keywords` VARCHAR(300) NOT NULL,
> `description` TEXT NOT NULL,
> `sku` VARCHAR(100) NOT NULL,
> -- This is the only "unique identifier given, none will be duplicates"
> `price` DECIMAL(10, 2) NOT NULL,
> `created` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
> `updatedat` TIMESTAMP NOT NULL DEFAULT '0000-00-00 00:00:00',
> `delete` TINYINT(4) NOT NULL DEFAULT '0',
> PRIMARY KEY (`sku`) ) ENGINE=myisam DEFAULT CHARSET=latin1;
>
> CREATE TABLE IF NOT EXISTS `temptable` LIKE `product_table`;
>
> TRUNCATE TABLE `temptable`; -- Remove data from temp table if for some
> reason it has data in it.
>
> LOAD DATA LOW_PRIORITY LOCAL INFILE "catalog.csv" INTO TABLE
> `temptable` FIELDS TERMINATED BY "," OPTIONALLY ENCLOSED BY """"
> LINES TERMINATED BY "\n" IGNORE 1 LINES (`PROGRAMNAME`, `NAME`,
> `KEYWORDS`, `DESCRIPTION`, `SKU`, `PRICE`);
>
>
> UPDATE `temptable` SET `delete` = 1; -- Set the delete field to
> true UPDATE `temptable` ttable
> INNER JOIN `product_table` mtable
> ON ( mtable.sku = ttable.sku ) SET mtable.programname = ttable.programname,
> mtable.name = ttable.name,
> mtable.keywords = ttable.keywords,
> mtable.description = ttable.description,
> mtable.sku = ttable.sku,
> mtable.price = ttable.price,
> mtable.created = ttable.created,
> mtable.updatedat = NOW(),-- Set Last Update
> mtable.delete = 0; -- Set Delete to NO
>
> -- Not sure what this is for... I'm LOST at this part...
> INSERT INTO `product_table` VALUES (`programname`,
> `name`,
> `keywords`,
> `description`,
> `sku`,
> `price`,
> `created`,
> `updatedat`,
> `delete`);
>
> -- This type of join requires alias as far as I know?
> SELECT `programname`,
> `name`,
> `keywords`,
> `description`,
> `sku`,
> `price`,
> `created`,
> `updatedat`,
> `delete` FROM `temptable` tmptable
> LEFT JOIN `product_table` maintbl
> ON tmptable.sku = maintbl.sku WHERE maintbl.sku IS NULL;
>
> DELETE FROM `product_table` WHERE `delete` = 0;
>
> TRUNCATE TABLE `temptable`; `` remove all the data from temporary
> table.