# class <class name="ClassName" (1) table="tableName" (2) discriminator-value="discriminator_value" (3) mutable="true|false" (4) schema="owner" (5) proxy="ProxyInterface" (6) dynamic-update="true|false" (7) dynamic-insert="true|false" (8) select-before-update="true|false" (9) polymorphism="implicit|explicit" (10) where="arbitrary sql where condition" (11) persister="PersisterClass" (12) batch-size="N" (13) optimistic-lock="none|version|dirty|all" (14) lazy="true|false" (15) abstract="true|false" (16) /> (1) name: The fully qualified .NET class name of the persistent class (or interface), including its assembly name. (2) table(optional - defaults to the unqualified class name): The name of its database table. (3) discriminator-value (optional - defaults to the class name): A value that distinguishes individual subclasses, used for polymorphic behaviour. Acceptable values include null and not null. (4) mutable (optional, defaults to true): Specifies that instances of the class are (not) mutable. (5) schema (optional): Override the schema name specified by the root <hibernate-mapping> element. (6) proxy (optional): Specifies an interface to use for lazy initializing proxies. You may specify the name of the class itself. (7) dynamic-update (optional, defaults to false): Specifies that UPDATE SQL should be generated at runtime and contain only those columns whose values have changed. (8) dynamic-insert (optional, defaults to false): Specifies that INSERT SQL should be generated at runtime and contain only the columns whose values are not null. (9) select-before-update (optional, defaults to false): Specifies that NHibernate should never perform an SQL UPDATE unless it is certain that an object is actually modified. In certain cases (actually, only when a transient object has been associated with a new session using update()), this means that NHibernate will perform an extra SQL SELECT to determine if an UPDATE is actually required. (10) polymorphism (optional, defaults to implicit): Determines whether implicit or explicit query polymorphism is used. (11) where (optional) specify an arbitrary SQL WHERE condition to be used when retrieving objects of this class (12) persister (optional): Specifies a custom IClassPersister. (13) batch-size (optional, defaults to 1) specify a "batch size" for fetching instances of this class by identifier. (14) optimistic-lock (optional, defaults to version): Determines the optimistic locking strategy. (15) lazy (optional): Lazy fetching may be completely disabled by setting lazy="false". (16) abstract (optional): Used to mark abstract superclasses in <union-subclass> hierarchies. # id <id name="PropertyName" (1) type="typename" (2) column="column_name" (3) unsaved-value="any|none|null|id_value" (4) access="field|property|nosetter|ClassName(5)"> <generator class="generatorClass"/> (1) name (optional): The name of the identifier property. (2) type (optional): A name that indicates the NHibernate type. (3) column (optional - defaults to the property name): The name of the primary key column. (4) unsaved-value (optional - defaults to a "sensible" value): An identifier property value that indicates that an instance is newly instantiated (unsaved), distinguishing it from transient instances that were saved or loaded in a previous session. (5) access (optional - defaults to property): The strategy NHibernate should use for accessing the property value. </id> # property <property name="propertyName" (1) column="column_name" (2) type="typename" (3) update="true|false" (4) insert="true|false" (4) formula="arbitrary SQL expression" (5) access="field|property|ClassName" (6) optimistic-lock="true|false" (7) generated="never|insert|always" (8) lazy="true|false" (9) /> (1) name: the name of the property of your class. (2) column (optional - defaults to the property name): the name of the mapped database table column. (3) type (optional): a name that indicates the NHibernate type. (4) update, insert (optional - defaults to true) : specifies that the mapped columns should be included in SQL UPDATE and/or INSERT statements. Setting both to false allows a pure "derived" property whose value is initialized from some other property that maps to the same column(s) or by a trigger or other application. (5) formula (optional): an SQL expression that defines the value for a computed property. Computed properties do not have a column mapping of their own. (6) access (optional - defaults to property): The strategy NHibernate should use for accessing the property value. (7) optimistic-lock (optional - defaults to true): Specifies that updates to this property do or do not require acquisition of the optimistic lock. In other words, determines if a version increment should occur when this property is dirty. (8) generated (optional - defaults to never): Specifies that this property value is actually generated by the database. See the discussion of Section 5.5, “Generated Properties”. (9) lazy (optional - defaults to false): Specifies that this property is lazy. A lazy property is not loaded when the object is initially loaded, unless the fetch mode has been overridden in a specific query. Values for lazy properties are loaded when any lazy property of the object is accessed. 原文：https://www.cnblogs.com/baily/p/9314438.html