Package org.apache.calcite.schema.impl

Class AbstractSchema

java.lang.Object
org.apache.calcite.schema.impl.AbstractSchema
All Implemented Interfaces:
Schema
Direct Known Subclasses:
CassandraSchema, CloneSchema, CsvSchema, DruidSchema, ElasticsearchSchema, GeodeSchema, GeodeSimpleSchema, InnodbSchema, JdbcCatalogSchema, MongoSchema, PigSchema, ReflectiveSchema, SplunkSchema, TpcdsSchema, TpchSchema
public class AbstractSchema extends Object implements Schema
Abstract implementation of Schema.

Behavior is as follows:

  • The schema has no tables unless you override getTableMap().
  • The schema has no functions unless you override getFunctionMultimap().
  • The schema has no sub-schemas unless you override getSubSchemaMap().
  • The schema is mutable unless you override isMutable().
  • The name and parent schema are as specified in the constructor arguments.

  • Constructor Details

    • AbstractSchema

      public AbstractSchema()

  • Method Details

    • isMutable

      public boolean isMutable()
      Description copied from interface: Schema
      Returns whether the user is allowed to create new tables, functions and sub-schemas in this schema, in addition to those returned automatically by methods such as Schema.getTable(String).

      Even if this method returns true, the maps are not modified. Calcite stores the defined objects in a wrapper object.

      Specified by:
      isMutable in interface Schema
      Returns:
      Whether the user is allowed to create new tables, functions and sub-schemas in this schema

    • snapshot

      public Schema snapshot(SchemaVersion version)
      Description copied from interface: Schema
      Returns the snapshot of this schema as of the specified time. The contents of the schema snapshot should not change over time.
      Specified by:
      snapshot in interface Schema
      Parameters:
      version - The current schema version
      Returns:
      the schema snapshot.

    • getExpression

      public Expression getExpression(@Nullable SchemaPlus parentSchema, String name)
      Description copied from interface: Schema
      Returns the expression by which this schema can be referenced in generated code.
      Specified by:
      getExpression in interface Schema
      Parameters:
      parentSchema - Parent schema
      name - Name of this schema
      Returns:
      Expression by which this schema can be referenced in generated code

    • getTableMap

      protected Map<String,Table> getTableMap()
      Returns a map of tables in this schema by name.

      The implementations of getTableNames() and getTable(String) depend on this map. The default implementation of this method returns the empty map. Override this method to change their behavior.

      Returns:
      Map of tables in this schema by name

    • getTableNames

      public final Set<String> getTableNames()
      Description copied from interface: Schema
      Returns the names of the tables in this schema.
      Specified by:
      getTableNames in interface Schema
      Returns:
      Names of the tables in this schema

    • getTable

      public final @Nullable Table getTable(String name)
      Description copied from interface: Schema
      Returns a table with a given name, or null if not found.
      Specified by:
      getTable in interface Schema
      Parameters:
      name - Table name
      Returns:
      Table, or null

    • getTypeMap

      protected Map<String,RelProtoDataType> getTypeMap()
      Returns a map of types in this schema by name.

      The implementations of getTypeNames() and getType(String) depend on this map. The default implementation of this method returns the empty map. Override this method to change their behavior.

      Returns:
      Map of types in this schema by name

    • getType

      public @Nullable RelProtoDataType getType(String name)
      Description copied from interface: Schema
      Returns a type with a given name, or null if not found.
      Specified by:
      getType in interface Schema
      Parameters:
      name - Table name
      Returns:
      Table, or null

    • getTypeNames

      public Set<String> getTypeNames()
      Description copied from interface: Schema
      Returns the names of the types in this schema.
      Specified by:
      getTypeNames in interface Schema
      Returns:
      Names of the tables in this schema

    • getFunctionMultimap

      protected com.google.common.collect.Multimap<String,Function> getFunctionMultimap()
      Returns a multi-map of functions in this schema by name. It is a multi-map because functions are overloaded; there may be more than one function in a schema with a given name (as long as they have different parameter lists).

      The implementations of getFunctionNames() and Schema.getFunctions(String) depend on this map. The default implementation of this method returns the empty multi-map. Override this method to change their behavior.

      Returns:
      Multi-map of functions in this schema by name

    • getFunctions

      public final Collection<Function> getFunctions(String name)
      Description copied from interface: Schema
      Returns a list of functions in this schema with the given name, or an empty list if there is no such function.
      Specified by:
      getFunctions in interface Schema
      Parameters:
      name - Name of function
      Returns:
      List of functions with given name, or empty list

    • getFunctionNames

      public final Set<String> getFunctionNames()
      Description copied from interface: Schema
      Returns the names of the functions in this schema.
      Specified by:
      getFunctionNames in interface Schema
      Returns:
      Names of the functions in this schema

    • getSubSchemaMap

      protected Map<String,Schema> getSubSchemaMap()
      Returns a map of sub-schemas in this schema by name.

      The implementations of getSubSchemaNames() and getSubSchema(String) depend on this map. The default implementation of this method returns the empty map. Override this method to change their behavior.

      Returns:
      Map of sub-schemas in this schema by name

    • getSubSchemaNames

      public final Set<String> getSubSchemaNames()
      Description copied from interface: Schema
      Returns the names of this schema's child schemas.
      Specified by:
      getSubSchemaNames in interface Schema
      Returns:
      Names of this schema's child schemas

    • getSubSchema

      public final @Nullable Schema getSubSchema(String name)
      Description copied from interface: Schema
      Returns a sub-schema with a given name, or null.
      Specified by:
      getSubSchema in interface Schema
      Parameters:
      name - Sub-schema name
      Returns:
      Sub-schema with a given name, or null