org.apache.calcite.sql.validate

Class ListScope

java.lang.Object

org.apache.calcite.sql.validate.DelegatingScope

org.apache.calcite.sql.validate.ListScope

All Implemented Interfaces:

SqlValidatorScope

Direct Known Subclasses:

JoinScope, MatchRecognizeScope, OverScope, PivotScope, SelectScope, UnpivotScope

public abstract class ListScope
extends DelegatingScope

Abstract base for a scope which is defined by a list of child namespaces and which inherits from a parent scope.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.calcite.sql.validate.SqlValidatorScope

SqlValidatorScope.EmptyPath, SqlValidatorScope.Path, SqlValidatorScope.Resolve, SqlValidatorScope.Resolved, SqlValidatorScope.ResolvedImpl, SqlValidatorScope.Step

Field Summary

Fields

Modifier and Type	Field and Description
List<org.apache.calcite.sql.validate.ScopeChild>	children List of child SqlValidatorNamespace objects and their names.

Fields inherited from class org.apache.calcite.sql.validate.DelegatingScope

parent, validator

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ListScope(SqlValidatorScope parent)

Method Summary

Modifier and Type	Method and Description
void	addChild(SqlValidatorNamespace ns, String alias, boolean nullable) Registers a relation in this scope.
void	findAliases(Collection<SqlMoniker> result) Collects the SqlMonikers of all table aliases (uses of tables in query FROM clauses) available in this scope.
void	findAllColumnNames(List<SqlMoniker> result) Collects the SqlMonikers of all possible columns in this scope.
Pair<String,SqlValidatorNamespace>	findQualifyingTableName(String columnName, SqlNode ctx)
Map<String,org.apache.calcite.sql.validate.ScopeChild>	findQualifyingTableNames(String columnName, SqlNode ctx, SqlNameMatcher nameMatcher) Finds all table aliases which are implicitly qualifying an unqualified column name.
List<SqlValidatorNamespace>	getChildren() Returns an immutable list of child namespaces.
boolean	isChildNullable(int i) Whether the ith child namespace produces nullable result.
void	resolve(List<String> names, SqlNameMatcher nameMatcher, boolean deep, SqlValidatorScope.Resolved resolved) Looks up a node with a given name.
@Nullable RelDataType	resolveColumn(String columnName, SqlNode ctx) Resolves a single identifier to a column, and returns the datatype of that column.

Methods inherited from class org.apache.calcite.sql.validate.DelegatingScope

addColumnNames, fullyQualify, getMonotonicity, getOperandScope, getOrderList, getParent, getTableNamespace, getValidator, lookupWindow, nullifyType, resolveTable, validateExpr

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.calcite.sql.validate.SqlValidatorScope

getNode, isWithin

Field Detail

children

public final List<org.apache.calcite.sql.validate.ScopeChild> children

List of child SqlValidatorNamespace objects and their names.

Constructor Detail

ListScope

protected ListScope(SqlValidatorScope parent)

Method Detail

addChild

public void addChild(SqlValidatorNamespace ns,
                     String alias,
                     boolean nullable)

Description copied from interface: SqlValidatorScope

Registers a relation in this scope.

Specified by:

addChild in interface SqlValidatorScope

Overrides:

addChild in class DelegatingScope

Parameters:

ns - Namespace representing the result-columns of the relation

alias - Alias with which to reference the relation, must not be null

nullable - Whether this is a null-generating side of a join

getChildren

public List<SqlValidatorNamespace> getChildren()

Returns an immutable list of child namespaces.

Returns:

list of child namespaces

isChildNullable

public boolean isChildNullable(int i)

Whether the ith child namespace produces nullable result. For example, in below query,

   SELECT *
   FROM EMPS
   LEFT OUTER JOIN DEPT
 

the namespace which corresponding to 'DEPT' is nullable.

Parameters:

i - The child index.

Returns:

Whether it's nullable.

findAllColumnNames

public void findAllColumnNames(List<SqlMoniker> result)

Description copied from interface: SqlValidatorScope

Collects the SqlMonikers of all possible columns in this scope.

Specified by:

findAllColumnNames in interface SqlValidatorScope

Overrides:

findAllColumnNames in class DelegatingScope

Parameters:

result - an array list of strings to add the result to

findAliases

public void findAliases(Collection<SqlMoniker> result)

Description copied from interface: SqlValidatorScope

Collects the SqlMonikers of all table aliases (uses of tables in query FROM clauses) available in this scope.

Specified by:

findAliases in interface SqlValidatorScope

Overrides:

findAliases in class DelegatingScope

Parameters:

result - a list of monikers to add the result to

findQualifyingTableName

public Pair<String,SqlValidatorNamespace> findQualifyingTableName(String columnName,
                                                                  SqlNode ctx)

Specified by:

findQualifyingTableName in interface SqlValidatorScope

Overrides:

findQualifyingTableName in class DelegatingScope

findQualifyingTableNames

public Map<String,org.apache.calcite.sql.validate.ScopeChild> findQualifyingTableNames(String columnName,
                                                                                       SqlNode ctx,
                                                                                       SqlNameMatcher nameMatcher)

Description copied from interface: SqlValidatorScope

Finds all table aliases which are implicitly qualifying an unqualified column name.

This method is only implemented in scopes (such as SelectScope) which can be the context for name-resolution. In scopes such as IdentifierNamespace, it throws UnsupportedOperationException.

Specified by:

findQualifyingTableNames in interface SqlValidatorScope

Overrides:

findQualifyingTableNames in class DelegatingScope

Parameters:

columnName - Column name

ctx - Validation context, to appear in any error thrown

nameMatcher - Name matcher

Returns:

Map of applicable table alias and namespaces, never null, empty if no aliases found

resolve

public void resolve(List<String> names,
                    SqlNameMatcher nameMatcher,
                    boolean deep,
                    SqlValidatorScope.Resolved resolved)

Description copied from interface: SqlValidatorScope

Looks up a node with a given name. Returns null if none is found.

Specified by:

resolve in interface SqlValidatorScope

Overrides:

resolve in class DelegatingScope

Parameters:

names - Name of node to find, maybe partially or fully qualified

nameMatcher - Name matcher

deep - Whether to look more than one level deep

resolved - Callback wherein to write the match(es) we find

resolveColumn

public @Nullable RelDataType resolveColumn(String columnName,
                                           SqlNode ctx)

Description copied from interface: SqlValidatorScope

Resolves a single identifier to a column, and returns the datatype of that column.

If it cannot find the column, returns null. If the column is ambiguous, throws an error with context ctx.

Specified by:

resolveColumn in interface SqlValidatorScope

Overrides:

resolveColumn in class DelegatingScope

Parameters:

columnName - Name of column

ctx - Context for exception

Returns:

Type of column, if found and unambiguous; null if not found