DataContext (Apache Calcite API)

All Known Implementing Classes:

CalciteConnectionImpl.DataContextImpl, CalciteConnectionImpl.SlimDataContext, Schemas.DummyDataContext, VisitorDataContext
```
public interface DataContext
```
Runtime context allowing access to the tables in a database.

Nested Class Summary

Nested Classes
Modifier and Type Interface Description

static class DataContext.Variable
Variable that may be asked for in a call to get(java.lang.String).

Field Summary

Fields
Modifier and Type Field Description

static ParameterExpression ROOT

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`java.lang.Object`	`get(java.lang.String name)`	Returns a context variable.
`QueryProvider`	`getQueryProvider()`	Returns the query provider.
`SchemaPlus`	`getRootSchema()`	Returns a sub-schema with a given name, or null.
`JavaTypeFactory`	`getTypeFactory()`	Returns the type factory.

- Field Detail
  - ROOT
```
static final ParameterExpression ROOT
```
- Method Detail
  - getRootSchema
```
SchemaPlus getRootSchema()
```
    Returns a sub-schema with a given name, or null.
  - getTypeFactory
```
JavaTypeFactory getTypeFactory()
```
    Returns the type factory.
  - getQueryProvider
```
QueryProvider getQueryProvider()
```
    Returns the query provider.
  - get
```
java.lang.Object get(java.lang.String name)
```
    Returns a context variable.
    Supported variables include: "sparkContext", "currentTimestamp", "localTimestamp".
    
    Parameters:
    
    name - Name of variable