Package org.apache.calcite.adapter.mongodb

Class MongoTable

java.lang.Object

org.apache.calcite.schema.impl.AbstractTable

org.apache.calcite.adapter.java.AbstractQueryableTable

org.apache.calcite.adapter.mongodb.MongoTable

All Implemented Interfaces:

QueryableTable, Table, TranslatableTable, Wrapper

public class MongoTable
extends AbstractQueryableTable
implements TranslatableTable

Table based on a MongoDB collection.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MongoTable.MongoQueryable<T>	Implementation of Queryable based on a MongoTable.

Field Summary

Fields

Modifier and Type	Field	Description
private java.lang.String	collectionName

Fields inherited from class org.apache.calcite.adapter.java.AbstractQueryableTable

elementType

Constructor Summary

Constructors

Constructor	Description
MongoTable(java.lang.String collectionName)	Creates a MongoTable.

Method Summary

Modifier and Type	Method	Description
private Enumerable<java.lang.Object>	aggregate(com.mongodb.client.MongoDatabase mongoDb, java.util.List<java.util.Map.Entry<java.lang.String,java.lang.Class>> fields, java.util.List<java.lang.String> operations)	Executes an "aggregate" operation on the underlying collection.
<T> Queryable<T>	asQueryable(QueryProvider queryProvider, SchemaPlus schema, java.lang.String tableName)	Converts this table into a Queryable.
private Enumerable<java.lang.Object>	find(com.mongodb.client.MongoDatabase mongoDb, java.lang.String filterJson, java.lang.String projectJson, java.util.List<java.util.Map.Entry<java.lang.String,java.lang.Class>> fields)	Executes a "find" operation on the underlying collection.
RelDataType	getRowType(RelDataTypeFactory typeFactory)	Returns this table's row type.
private static java.lang.Integer	parseIntString(java.lang.String valueString)	Helper method to strip non-numerics from a string.
RelNode	toRel(RelOptTable.ToRelContext context, RelOptTable relOptTable)	Converts this table into a relational expression.
java.lang.String	toString()

Methods inherited from class org.apache.calcite.adapter.java.AbstractQueryableTable

getElementType, getExpression

Methods inherited from class org.apache.calcite.schema.impl.AbstractTable

getJdbcTableType, getStatistic, isRolledUp, rolledUpColumnValidInsideAgg, unwrap

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.calcite.schema.Table

getJdbcTableType, getStatistic, isRolledUp, rolledUpColumnValidInsideAgg

Field Detail

collectionName

private final java.lang.String collectionName

Constructor Detail

MongoTable

MongoTable(java.lang.String collectionName)

Creates a MongoTable.

Method Detail

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getRowType

public RelDataType getRowType(RelDataTypeFactory typeFactory)

Description copied from interface: Table

Returns this table's row type.

This is a struct type whose fields describe the names and types of the columns in this table.

The implementer must use the type factory provided. This ensures that the type is converted into a canonical form; other equal types in the same query will use the same object.

Specified by:

getRowType in interface Table

Parameters:

typeFactory - Type factory with which to create the type

Returns:

Row type

asQueryable

public <T> Queryable<T> asQueryable(QueryProvider queryProvider,
                                    SchemaPlus schema,
                                    java.lang.String tableName)

Description copied from interface: QueryableTable

Converts this table into a Queryable.

Specified by:

asQueryable in interface QueryableTable

toRel

public RelNode toRel(RelOptTable.ToRelContext context,
                     RelOptTable relOptTable)

Description copied from interface: TranslatableTable

Converts this table into a relational expression.

Specified by:

toRel in interface TranslatableTable

find

private Enumerable<java.lang.Object> find(com.mongodb.client.MongoDatabase mongoDb,
                                          java.lang.String filterJson,
                                          java.lang.String projectJson,
                                          java.util.List<java.util.Map.Entry<java.lang.String,java.lang.Class>> fields)

Executes a "find" operation on the underlying collection.

For example, zipsTable.find("{state: 'OR'}", "{city: 1, zipcode: 1}")

Parameters:

mongoDb - MongoDB connection

filterJson - Filter JSON string, or null

projectJson - Project JSON string, or null

fields - List of fields to project; or null to return map

Returns:

Enumerator of results

aggregate

private Enumerable<java.lang.Object> aggregate(com.mongodb.client.MongoDatabase mongoDb,
                                               java.util.List<java.util.Map.Entry<java.lang.String,java.lang.Class>> fields,
                                               java.util.List<java.lang.String> operations)

Executes an "aggregate" operation on the underlying collection.

For example: zipsTable.aggregate( "{$filter: {state: 'OR'}", "{$group: {_id: '$city', c: {$sum: 1}, p: {$sum: '$pop'}}}")

Parameters:

mongoDb - MongoDB connection

fields - List of fields to project; or null to return map

operations - One or more JSON strings

Returns:

Enumerator of results

parseIntString

private static java.lang.Integer parseIntString(java.lang.String valueString)

Helper method to strip non-numerics from a string.

Currently used to determine mongod versioning numbers from buildInfo.versionArray for use in aggregate method logic.