重要的是要理解,在这个场景中,many-to-many 不是指多对多关系,而是指关系中的多对多基数类型。 关系的基数和列的基数有不同的含义,前者用于划分关系的类型,后者指列中不重复值的数量。如果不是特别说明,基数一般指后者。
重要的是要理解,在这个场景中,many-to-many 不是指多对多关系,而是指关系中的多对多基数类型。 关系的基数和列的基数有不同的含义,前者用于划分关系的类型,后者指列中不重复值的数量。如果不是特别说明,基数一般指后者。
MANY_TO_MANY Enum value ManyToMany. ONE_TO_MANY Enum value OneToMany. ONE_TO_ONE Enum value OneToOne.Methods inherited from java.lang.EnumvalueOf clone compareTo describeConstable equals finalize getDeclaringClass hashCode name ordinal toString Methods inherited from java.lang.Objectget...
many-to-many M:M At one moment in time, any one project can have many employees assigned to it (or have no employees). Also, any one employee can be assigned to many projects (or be assigned to no projects). one-to-many 1:M At one moment in time, any one project can have many...
美 英[kɑːdɪ'nælɪtɪ] n.〔数〕基数 网络基数性;势;基数或势 英汉 网络释义 n. 1. 〔数〕基数 释义: 全部,〔数〕基数,基数性,势,基数或势
Cardinality: how many or how few unique values there are for the shared field (uniqueness). For more information, see the next section. Referential Integrity: a value in one table is guaranteed to have a match in the other table. In other words, there can’t be a record in one table...
CAUTION: Remember that every unique combination of key-value label pairs represents a new time series, which can dramatically increase the amount of data stored. Do not use labels to store dimensions with high cardinality (many different label values), such as user IDs, email addresses, or othe...
The cardinality of A, also can be abbrevated as IAl, is a measure of how many different ...
Thus, for English speakers, given the set “apple, apple, apple, apple, apple” and the query “How many?”, the cardinality of the set is represented by “five.”“Apple” can be replaced with anything, from a subatomic particle to a planet, to sounds or actions, and the response ...
Fields Développer la table NameValueDescription Many 0 Relationship is Many-to-One. One 1 Relationship is One-to-One. Remarks Indicates if related attribute has many-to-one or one-to-one relationship with this attribute. Applies to ProduitVersions Analysis Services SDK for .NET latest Dans...