Question

private static BufferedImage matToBufferedImage(Mat original)
{
    BufferedImage image = null;
    int width = original.width(), height = original.height(), channels = original.channels();
    byte[] sourcePixels = new byte[width * height * channels];

    original.get(0, 0, sourcePixels);

    if (original.channels() > 1)
    {
        image = new BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR);
    }
    else
    {
        image = new BufferedImage(width, height, BufferedImage.TYPE_BYTE_GRAY);
    }

    final byte[] targetPixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();
    System.arraycopy(sourcePixels, 0, targetPixels, 0, sourcePixels.length);

    return image;
}

上述查询会提取包含产品“ 35365”和“ 34299”的分类类别

SELECT DISTINCT {c2.name} 
FROM 
    {BrandCategory AS c  
    JOIN CategoryProductRelation AS c2p  
    ON  {c.pk} = {c2p.source}  
    JOIN Product AS p  
    ON  {c2p.target} = {p.pk}  
    JOIN CategoryProductRelation AS c2p2  
    ON  {p.pk} = {c2p2.target}  
    JOIN TaxonomyCategory AS c2 ON {c2.pk} = {c2p2.source} 
    JOIN CatalogVersion AS cat 
    ON {c.catalogVersion} = {cat.PK}} 
WHERE 
    {c.code} = 'brand-MCH' 
    AND{cat.version} = 'Online' 
    AND {c2.code} NOT LIKE'%webFamily%' 
    AND {p.code} IN ('35365','34299')

现在的要求是删除所有其他分类法类别，这意味着这些类别不包含产品“ 35365”和“ 34299”

尝试1 ：（失败）（不输入）

Result:
Passenger
Touring
All-Season
Truck

All Categories:
All-Season
Performance
Passenger
Winter
Touring
Summer
Truck
All-Terrain
Competition
Lawn

尝试2 ：（失败）（不存在）

SELECT  DISTINCT {c2.name}
    FROM  {BrandCategory AS c
    JOIN  CategoryProductRelation AS c2p  ON {c.pk} = {c2p.source}
    JOIN  Product AS p  ON {c2p.target} = {p.pk}
    JOIN  CategoryProductRelation AS c2p2  ON {p.pk} = {c2p2.target}
    JOIN  TaxonomyCategory AS c2  ON {c2.pk} = {c2p2.source}
    JOIN  CatalogVersion AS cat  ON {c.catalogVersion} = {cat.PK}}
    WHERE  {c.code} = 'brand-MCH' AND{cat.version} = 'Online'
      AND  {c2.code} NOT LIKE'%webFamily%'
      AND  {p.code} NOT IN ('35365','34299')

尝试3 ：（失败）（不在子查询中）

SELECT  DISTINCT {c2.name}
    FROM  {BrandCategory AS c
    JOIN  CategoryProductRelation AS c2p  ON {c.pk} = {c2p.source}
    JOIN  Product AS p  ON {c2p.target} = {p.pk}
    JOIN  CategoryProductRelation AS c2p2  ON {p.pk} = {c2p2.target}
    JOIN  TaxonomyCategory AS c2  ON {c2.pk} = {c2p2.source}
    JOIN  CatalogVersion AS cat  ON {c.catalogVersion} = {cat.PK}}
    WHERE  {c.code} = 'brand-MCH' AND{cat.version} = 'Online'
      AND  {c2.code} NOT LIKE'%webFamily%'
      AND  {c2.code}
      AND  NOT EXISTS ({{
        SELECT  DISTINCT {c3.name}
            FROM  {BrandCategory AS c
            JOIN  CategoryProductRelation AS c2p  ON {c.pk} = {c2p.source}
            JOIN  Product AS p  ON {c2p.target} = {p.pk}
            JOIN  CategoryProductRelation AS c2p2  ON {p.pk} = {c2p2.target}
            JOIN  TaxonomyCategory AS c3  ON {c3.pk} = {c2p2.source}
            JOIN  CatalogVersion AS cat  ON {c.catalogVersion} = {cat.PK}}
            WHERE  {c3.name}={c2.name}
              AND  {c.code} = 'brand-MCH' AND{cat.version} = 'Online'
              AND  {c3.code} NOT LIKE'%webFamily%'
              AND  {p.code} IN ('35365','34299')}}
                      )

...

SELECT  DISTINCT {c2.name}
    FROM  {BrandCategory AS c
    JOIN  CategoryProductRelation AS c2p  ON {c.pk} = {c2p.source}
    JOIN  Product AS p  ON {c2p.target} = {p.pk}
    JOIN  CategoryProductRelation AS c2p2  ON {p.pk} = {c2p2.target}
    JOIN  TaxonomyCategory AS c2  ON {c2.pk} = {c2p2.source}
    JOIN  CatalogVersion AS cat  ON {c.catalogVersion} = {cat.PK}}
    WHERE  {c.code} = 'brand-MCH' AND{cat.version} = 'Online'
      AND  {c2.code} NOT LIKE'%webFamily%'
      AND  {c2.name} NOT IN ({{
        SELECT  DISTINCT {c2.name}
            FROM  {BrandCategory AS c
            JOIN  CategoryProductRelation AS c2p  ON {c.pk} = {c2p.source}
            JOIN  Product AS p  ON {c2p.target} = {p.pk}
            JOIN  CategoryProductRelation AS c2p2  ON {p.pk} = {c2p2.target}
            JOIN  TaxonomyCategory AS c2  ON {c2.pk} = {c2p2.source}
            JOIN  CatalogVersion AS cat  ON {c.catalogVersion} = {cat.PK}}
            WHERE  {c.code} = 'brand-MCH' AND{cat.version} = 'Online'
              AND  {c2.code} NOT LIKE'%webFamily%'
              AND  {p.code} IN ('35365','34299')}}
                          )

请提供最佳查询，以帮助控制性能，以获取不包含的类别。

此外，如果有一种方法可以得到带有某些标志的所有类别，以区分哪些产品包含真实与否，那将是绝对的黄金，因为在这里，我们要两次命中数据库以获取包含并随后包含该类别的产品不要包含按需呼叫

注意：这些本质上是SQL查询，但仅对这些花括号进行了少许修改，以支持Hybris Framework中的灵活搜索查询格式

Answer 1

查询 -
1.使用NOT IN-
SELECT {c.code} FROM {Product as p join CategoryProductRelation as c2p on {c2p.target} = {p.pk} join Category as c on {c2p.source} = {c.pk}} WHERE {p.code} NOT IN ('35365','34299')

使用不存在-
SELECT {c.code} FROM {CategoryProductRelation as c2p join Category as c on {c2p.source} = {c.pk}} WHERE NOT EXISTS ({{SELECT {p.code} FROM {Product as p} WHERE {p.code} IN ('35365','34299') and {c2p.target}={p.pk}}})
使用子查询-
SELECT {c.code} FROM {Product as p join CategoryProductRelation as c2p on {c2p.target} = {p.pk} join Category as c on {c2p.source} = {c.pk}} WHERE {p.pk} IN ({{SELECT {pk} FROM {Product} WHERE {code} IN ('35365','34299')}})

Answer 2

首先查看NOT EXISTS和NOT IN是否给出正确的值。

对于EXISTS，请勿打扰DISTINCT，也不要指定列。这足够了：

NOT EXISTS ( SELECT 1 FROM ... )

剔除与该问题无关的所有JOIN。这样可以更容易发现问题所在。

大括号是什么？也许您应该删除[mysql]标签？

SQL如何获取不包含产品的类别？

2 个答案: