org.apache.calcite.linq4j

类 QueryProviderImpl

java.lang.Object

org.apache.calcite.linq4j.QueryProviderImpl

所有已实现的接口:

QueryProvider

public abstract class QueryProviderImpl
extends Object
implements QueryProvider

Partial implementation of QueryProvider.

Derived class needs to implement QueryProvider.executeQuery(org.apache.calcite.linq4j.Queryable<T>).

嵌套类概要

嵌套类

限定符和类型	类和说明
static class	QueryProviderImpl.QueryableImpl<T> Binds an expression to this query provider.

构造器概要

构造器

限定符	构造器和说明
protected	QueryProviderImpl() Creates a QueryProviderImpl.

方法概要

限定符和类型	方法和说明
<T> Queryable<T>	createQuery(Expression expression, Class<T> rowType) Constructs a Queryable object that can evaluate the query represented by a specified expression tree.
<T> Queryable<T>	createQuery(Expression expression, Type rowType) Constructs a Queryable object that can evaluate the query represented by a specified expression tree.
<T> T	execute(Expression expression, Class<T> type) Executes the query represented by a specified expression tree.
<T> T	execute(Expression expression, Type type) Executes the query represented by a specified expression tree.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

从接口继承的方法 org.apache.calcite.linq4j.QueryProvider

executeQuery

构造器详细资料

QueryProviderImpl

protected QueryProviderImpl()

Creates a QueryProviderImpl.

方法详细资料

createQuery

public <T> Queryable<T> createQuery(Expression expression,
                                    Class<T> rowType)

从接口复制的说明: QueryProvider

Constructs a Queryable object that can evaluate the query represented by a specified expression tree.

NOTE: The RawQueryable.getExpression() property of the returned Queryable object is equal to expression.

指定者:

createQuery 在接口中 QueryProvider

类型参数:

T - Row type

参数:

expression - Expression

rowType - Row type

返回:

Queryable

createQuery

public <T> Queryable<T> createQuery(Expression expression,
                                    Type rowType)

从接口复制的说明: QueryProvider

Constructs a Queryable object that can evaluate the query represented by a specified expression tree. The row type may contain generic information.

指定者:

createQuery 在接口中 QueryProvider

类型参数:

T - Row type

参数:

expression - Expression

rowType - Row type

返回:

Queryable

execute

public <T> T execute(Expression expression,
                     Class<T> type)

从接口复制的说明: QueryProvider

Executes the query represented by a specified expression tree.

This method executes queries that return a single value (instead of an enumerable sequence of values). Expression trees that represent queries that return enumerable results are executed when the Queryable object that contains the expression tree is enumerated.

The Queryable standard query operator methods that return singleton results call execute. They pass it a MethodCallExpression that represents a linq4j query.

指定者:

execute 在接口中 QueryProvider

execute

public <T> T execute(Expression expression,
                     Type type)

从接口复制的说明: QueryProvider

Executes the query represented by a specified expression tree. The row type may contain type parameters.

指定者:

execute 在接口中 QueryProvider