/**
* Validates the parse tree of a SQL statement, and provides semantic information about the parse
* tree.
*
* <p>To create an instance of the default validator implementation, call {@link
* SqlValidatorUtil#newValidator}.
*
* <h2>Visitor pattern</h2>
*
* <p>The validator interface is an instance of the {@link
* org.apache.calcite.util.Glossary#VISITOR_PATTERN visitor pattern}. Implementations of the {@link
* SqlNode#validate} method call the <code>validateXxx</code> method appropriate to the kind of
* node:
*
* <ul>
* <li>{@link SqlLiteral#validate(SqlValidator, SqlValidatorScope)} calls {@link
* #validateLiteral(org.apache.calcite.sql.SqlLiteral)};
* <li>{@link SqlCall#validate(SqlValidator, SqlValidatorScope)} calls {@link
* #validateCall(SqlCall, SqlValidatorScope)};
* <li>and so forth.
* </ul>
*
* <p>The {@link SqlNode#validateExpr(SqlValidator, SqlValidatorScope)} method is as {@link
* SqlNode#validate(SqlValidator, SqlValidatorScope)} but is called when the node is known to be a
* scalar expression.
*
* <h2>Scopes and namespaces</h2>
*
* <p>In order to resolve names to objects, the validator builds a map of the structure of the
* query. This map consists of two types of objects. A {@link SqlValidatorScope} describes the
* tables and columns accessible at a particular point in the query; and a {@link
* SqlValidatorNamespace} is a description of a data source used in a query.
*
* <p>There are different kinds of namespace for different parts of the query. for example {@link
* IdentifierNamespace} for table names, {@link SelectNamespace} for SELECT queries, {@link
* SetopNamespace} for UNION, EXCEPT and INTERSECT. A validator is allowed to wrap namespaces in
* other objects which implement {@link SqlValidatorNamespace}, so don't try to cast your namespace
* or use <code>instanceof</code>; use {@link SqlValidatorNamespace#unwrap(Class)} and {@link
* SqlValidatorNamespace#isWrapperFor(Class)} instead.
*
* <p>The validator builds the map by making a quick scan over the query when the root {@link
* SqlNode} is first provided. Thereafter, it supplies the correct scope or namespace object when it
* calls validation methods.
*
* <p>The methods {@link #getSelectScope}, {@link #getFromScope}, {@link #getWhereScope}, {@link
* #getGroupScope}, {@link #getHavingScope}, {@link #getOrderScope} and {@link #getJoinScope} get
* the correct scope to resolve names in a particular clause of a SQL statement.
*/
public interface SqlValidator {
/** Whether to follow the SQL standard strictly. */
boolean STRICT = Util.getBooleanProperty("calcite.strict.sql");
// ~ Methods ----------------------------------------------------------------
/**
* Returns the dialect of SQL (SQL:2003, etc.) this validator recognizes. Default is {@link
* SqlConformance#DEFAULT}.
*
* @return dialect of SQL this validator recognizes
*/
SqlConformance getConformance();
/**
* Returns the catalog reader used by this validator.
*
* @return catalog reader
*/
SqlValidatorCatalogReader getCatalogReader();
/**
* Returns the operator table used by this validator.
*
* @return operator table
*/
SqlOperatorTable getOperatorTable();
/**
* Validates an expression tree. You can call this method multiple times, but not reentrantly.
*
* @param topNode top of expression tree to be validated
* @return validated tree (possibly rewritten)
*/
SqlNode validate(SqlNode topNode);
/**
* Validates an expression tree. You can call this method multiple times, but not reentrantly.
*
* @param topNode top of expression tree to be validated
* @param nameToTypeMap map of simple name to {@link RelDataType}; used to resolve {@link
* SqlIdentifier} references
* @return validated tree (possibly rewritten)
*/
SqlNode validateParameterizedExpression(SqlNode topNode, Map<String, RelDataType> nameToTypeMap);
/**
* Checks that a query is valid.
*
* <p>Valid queries include:
*
* <ul>
* <li><code>SELECT</code> statement,
* <li>set operation (<code>UNION</code>, <code>INTERSECT</code>, <code>
* EXCEPT</code>)
* <li>identifier (e.g. representing use of a table in a FROM clause)
* <li>query aliased with the <code>AS</code> operator
* </ul>
*
* @param node Query node
* @param scope Scope in which the query occurs
* @param targetRowType Desired row type, must not be null, may be the data type 'unknown'.
* @throws RuntimeException if the query is not valid
*/
void validateQuery(SqlNode node, SqlValidatorScope scope, RelDataType targetRowType);
/**
* Returns the type assigned to a node by validation.
*
* @param node the node of interest
* @return validated type, never null
*/
RelDataType getValidatedNodeType(SqlNode node);
/**
* Returns the type assigned to a node by validation, or null if unknown. This allows for queries
* against nodes such as aliases, which have no type of their own. If you want to assert that the
* node of interest must have a type, use {@link #getValidatedNodeType} instead.
*
* @param node the node of interest
* @return validated type, or null if unknown or not applicable
*/
RelDataType getValidatedNodeTypeIfKnown(SqlNode node);
/**
* Resolves an identifier to a fully-qualified name.
*
* @param id Identifier
* @param scope Naming scope
*/
void validateIdentifier(SqlIdentifier id, SqlValidatorScope scope);
/**
* Validates a literal.
*
* @param literal Literal
*/
void validateLiteral(SqlLiteral literal);
/**
* Validates a {@link SqlIntervalQualifier}
*
* @param qualifier Interval qualifier
*/
void validateIntervalQualifier(SqlIntervalQualifier qualifier);
/**
* Validates an INSERT statement.
*
* @param insert INSERT statement
*/
void validateInsert(SqlInsert insert);
/**
* Validates an UPDATE statement.
*
* @param update UPDATE statement
*/
void validateUpdate(SqlUpdate update);
/**
* Validates a DELETE statement.
*
* @param delete DELETE statement
*/
void validateDelete(SqlDelete delete);
/**
* Validates a MERGE statement.
*
* @param merge MERGE statement
*/
void validateMerge(SqlMerge merge);
/**
* Validates a data type expression.
*
* @param dataType Data type
*/
void validateDataType(SqlDataTypeSpec dataType);
/**
* Validates a dynamic parameter.
*
* @param dynamicParam Dynamic parameter
*/
void validateDynamicParam(SqlDynamicParam dynamicParam);
/**
* Validates the right-hand side of an OVER expression. It might be either an {@link SqlIdentifier
* identifier} referencing a window, or an {@link SqlWindow inline window specification}.
*
* @param windowOrId SqlNode that can be either SqlWindow with all the components of a window spec
* or a SqlIdentifier with the name of a window spec.
* @param scope Naming scope
* @param call the SqlNode if a function call if the window is attached to one.
*/
void validateWindow(SqlNode windowOrId, SqlValidatorScope scope, SqlCall call);
/**
* Validates a call to an operator.
*
* @param call Operator call
* @param scope Naming scope
*/
void validateCall(SqlCall call, SqlValidatorScope scope);
/**
* Validates parameters for aggregate function.
*
* @param aggCall Function containing COLUMN_LIST parameter
* @param filter Filter, or null
* @param scope Syntactic scope
*/
void validateAggregateParams(SqlCall aggCall, SqlNode filter, SqlValidatorScope scope);
/**
* Validates a COLUMN_LIST parameter
*
* @param function function containing COLUMN_LIST parameter
* @param argTypes function arguments
* @param operands operands passed into the function call
*/
void validateColumnListParams(
SqlFunction function, List<RelDataType> argTypes, List<SqlNode> operands);
/**
* Derives the type of a node in a given scope. If the type has already been inferred, returns the
* previous type.
*
* @param scope Syntactic scope
* @param operand Parse tree node
* @return Type of the SqlNode. Should never return <code>NULL</code>
*/
RelDataType deriveType(SqlValidatorScope scope, SqlNode operand);
/**
* Adds "line x, column y" context to a validator exception.
*
* <p>Note that the input exception is checked (it derives from {@link Exception}) and the output
* exception is unchecked (it derives from {@link RuntimeException}). This is intentional -- it
* should remind code authors to provide context for their validation errors.
*
* @param node The place where the exception occurred, not null
* @param e The validation error
* @return Exception containing positional information, never null
*/
CalciteContextException newValidationError(
SqlNode node, Resources.ExInst<SqlValidatorException> e);
/**
* Returns whether a SELECT statement is an aggregation. Criteria are: (1) contains GROUP BY, or
* (2) contains HAVING, or (3) SELECT or ORDER BY clause contains aggregate functions. (Windowed
* aggregate functions, such as <code>SUM(x) OVER w</code>, don't count.)
*
* @param select SELECT statement
* @return whether SELECT statement is an aggregation
*/
boolean isAggregate(SqlSelect select);
/**
* Returns whether a select list expression is an aggregate function.
*
* @param selectNode Expression in SELECT clause
* @return whether expression is an aggregate function
*/
@Deprecated // to be removed before 2.0
boolean isAggregate(SqlNode selectNode);
/**
* Converts a window specification or window name into a fully-resolved window specification. For
* example, in <code>SELECT sum(x) OVER (PARTITION
* BY x ORDER BY y), sum(y) OVER w1, sum(z) OVER (w ORDER BY y) FROM t
* WINDOW w AS (PARTITION BY x)</code> all aggregations have the same resolved window
* specification <code>(PARTITION BY x ORDER BY y)</code>.
*
* @param windowOrRef Either the name of a window (a {@link SqlIdentifier}) or a window
* specification (a {@link SqlWindow}).
* @param scope Scope in which to resolve window names
* @param populateBounds Whether to populate bounds. Doing so may alter the definition of the
* window. It is recommended that populate bounds when translating to physical algebra, but
* not when validating.
* @return A window
* @throws RuntimeException Validation exception if window does not exist
*/
SqlWindow resolveWindow(SqlNode windowOrRef, SqlValidatorScope scope, boolean populateBounds);
/**
* Finds the namespace corresponding to a given node.
*
* <p>For example, in the query <code>SELECT * FROM (SELECT * FROM t), t1 AS
* alias</code>, the both items in the FROM clause have a corresponding namespace.
*
* @param node Parse tree node
* @return namespace of node
*/
SqlValidatorNamespace getNamespace(SqlNode node);
/**
* Derives an alias for an expression. If no alias can be derived, returns null if <code>ordinal
* </code> is less than zero, otherwise generates an alias <code>EXPR$<i>ordinal</i></code>.
*
* @param node Expression
* @param ordinal Ordinal of expression
* @return derived alias, or null if no alias can be derived and ordinal is less than zero
*/
String deriveAlias(SqlNode node, int ordinal);
/**
* Returns a list of expressions, with every occurrence of "*" or "TABLE.*" expanded.
*
* @param selectList Select clause to be expanded
* @param query Query
* @param includeSystemVars Whether to include system variables
* @return expanded select clause
*/
SqlNodeList expandStar(SqlNodeList selectList, SqlSelect query, boolean includeSystemVars);
/**
* Returns the scope that expressions in the WHERE and GROUP BY clause of this query should use.
* This scope consists of the tables in the FROM clause, and the enclosing scope.
*
* @param select Query
* @return naming scope of WHERE clause
*/
SqlValidatorScope getWhereScope(SqlSelect select);
/**
* Returns the type factory used by this validator.
*
* @return type factory
*/
RelDataTypeFactory getTypeFactory();
/**
* Saves the type of a {@link SqlNode}, now that it has been validated.
*
* @param node A SQL parse tree node, never null
* @param type Its type; must not be null
* @deprecated This method should not be in the {@link SqlValidator} interface. The validator
* should drive the type-derivation process, and store nodes' types when they have been
* derived.
*/
void setValidatedNodeType(SqlNode node, RelDataType type);
/**
* Removes a node from the set of validated nodes
*
* @param node node to be removed
*/
void removeValidatedNodeType(SqlNode node);
/**
* Returns an object representing the "unknown" type.
*
* @return unknown type
*/
RelDataType getUnknownType();
/**
* Returns the appropriate scope for validating a particular clause of a SELECT statement.
*
* <p>Consider
*
* <blockquote>
*
* <pre><code>SELECT *
* FROM foo
* WHERE EXISTS (
* SELECT deptno AS x
* FROM emp
* JOIN dept ON emp.deptno = dept.deptno
* WHERE emp.deptno = 5
* GROUP BY deptno
* ORDER BY x)</code></pre>
*
* </blockquote>
*
* <p>What objects can be seen in each part of the sub-query?
*
* <ul>
* <li>In FROM ({@link #getFromScope} , you can only see 'foo'.
* <li>In WHERE ({@link #getWhereScope}), GROUP BY ({@link #getGroupScope}), SELECT ({@code
* getSelectScope}), and the ON clause of the JOIN ({@link #getJoinScope}) you can see
* 'emp', 'dept', and 'foo'.
* <li>In ORDER BY ({@link #getOrderScope}), you can see the column alias 'x'; and tables 'emp',
* 'dept', and 'foo'.
* </ul>
*
* @param select SELECT statement
* @return naming scope for SELECT statement
*/
SqlValidatorScope getSelectScope(SqlSelect select);
/**
* Returns the scope for resolving the SELECT, GROUP BY and HAVING clauses. Always a {@link
* SelectScope}; if this is an aggregation query, the {@link AggregatingScope} is stripped away.
*
* @param select SELECT statement
* @return naming scope for SELECT statement, sans any aggregating scope
*/
SelectScope getRawSelectScope(SqlSelect select);
/**
* Returns a scope containing the objects visible from the FROM clause of a query.
*
* @param select SELECT statement
* @return naming scope for FROM clause
*/
SqlValidatorScope getFromScope(SqlSelect select);
/**
* Returns a scope containing the objects visible from the ON and USING sections of a JOIN clause.
*
* @param node The item in the FROM clause which contains the ON or USING expression
* @return naming scope for JOIN clause
* @see #getFromScope
*/
SqlValidatorScope getJoinScope(SqlNode node);
/**
* Returns a scope containing the objects visible from the GROUP BY clause of a query.
*
* @param select SELECT statement
* @return naming scope for GROUP BY clause
*/
SqlValidatorScope getGroupScope(SqlSelect select);
/**
* Returns a scope containing the objects visible from the HAVING clause of a query.
*
* @param select SELECT statement
* @return naming scope for HAVING clause
*/
SqlValidatorScope getHavingScope(SqlSelect select);
/**
* Returns the scope that expressions in the SELECT and HAVING clause of this query should use.
* This scope consists of the FROM clause and the enclosing scope. If the query is aggregating,
* only columns in the GROUP BY clause may be used.
*
* @param select SELECT statement
* @return naming scope for ORDER BY clause
*/
SqlValidatorScope getOrderScope(SqlSelect select);
/**
* Declares a SELECT expression as a cursor.
*
* @param select select expression associated with the cursor
* @param scope scope of the parent query associated with the cursor
*/
void declareCursor(SqlSelect select, SqlValidatorScope scope);
/** Pushes a new instance of a function call on to a function call stack. */
void pushFunctionCall();
/** Removes the topmost entry from the function call stack. */
void popFunctionCall();
/**
* Retrieves the name of the parent cursor referenced by a column list parameter.
*
* @param columnListParamName name of the column list parameter
* @return name of the parent cursor
*/
String getParentCursor(String columnListParamName);
/**
* Enables or disables expansion of identifiers other than column references.
*
* @param expandIdentifiers new setting
*/
void setIdentifierExpansion(boolean expandIdentifiers);
/**
* Enables or disables expansion of column references. (Currently this does not apply to the ORDER
* BY clause; may be fixed in the future.)
*
* @param expandColumnReferences new setting
*/
void setColumnReferenceExpansion(boolean expandColumnReferences);
/** @return whether column reference expansion is enabled */
boolean getColumnReferenceExpansion();
/**
* Sets how NULL values should be collated if an ORDER BY item does not contain NULLS FIRST or
* NULLS LAST.
*/
void setDefaultNullCollation(NullCollation nullCollation);
/**
* Returns how NULL values should be collated if an ORDER BY item does not contain NULLS FIRST or
* NULLS LAST.
*/
NullCollation getDefaultNullCollation();
/**
* Returns expansion of identifiers.
*
* @return whether this validator should expand identifiers
*/
boolean shouldExpandIdentifiers();
/**
* Enables or disables rewrite of "macro-like" calls such as COALESCE.
*
* @param rewriteCalls new setting
*/
void setCallRewrite(boolean rewriteCalls);
/**
* Derives the type of a constructor.
*
* @param scope Scope
* @param call Call
* @param unresolvedConstructor TODO
* @param resolvedConstructor TODO
* @param argTypes Types of arguments
* @return Resolved type of constructor
*/
RelDataType deriveConstructorType(
SqlValidatorScope scope,
SqlCall call,
SqlFunction unresolvedConstructor,
SqlFunction resolvedConstructor,
List<RelDataType> argTypes);
/**
* Handles a call to a function which cannot be resolved. Returns a an appropriately descriptive
* error, which caller must throw.
*
* @param call Call
* @param unresolvedFunction Overloaded function which is the target of the call
* @param argTypes Types of arguments
* @param argNames Names of arguments, or null if call by position
*/
CalciteException handleUnresolvedFunction(
SqlCall call,
SqlFunction unresolvedFunction,
List<RelDataType> argTypes,
List<String> argNames);
/**
* Expands an expression in the ORDER BY clause into an expression with the same semantics as
* expressions in the SELECT clause.
*
* <p>This is made necessary by a couple of dialect 'features':
*
* <ul>
* <li><b>ordinal expressions</b>: In "SELECT x, y FROM t ORDER BY 2", the expression "2" is
* shorthand for the 2nd item in the select clause, namely "y".
* <li><b>alias references</b>: In "SELECT x AS a, y FROM t ORDER BY a", the expression "a" is
* shorthand for the item in the select clause whose alias is "a"
* </ul>
*
* @param select Select statement which contains ORDER BY
* @param orderExpr Expression in the ORDER BY clause.
* @return Expression translated into SELECT clause semantics
*/
SqlNode expandOrderExpr(SqlSelect select, SqlNode orderExpr);
/**
* Expands an expression.
*
* @param expr Expression
* @param scope Scope
* @return Expanded expression
*/
SqlNode expand(SqlNode expr, SqlValidatorScope scope);
/**
* Returns whether a field is a system field. Such fields may have particular properties such as
* sortedness and nullability.
*
* <p>In the default implementation, always returns {@code false}.
*
* @param field Field
* @return whether field is a system field
*/
boolean isSystemField(RelDataTypeField field);
/**
* Returns a description of how each field in the row type maps to a catalog, schema, table and
* column in the schema.
*
* <p>The returned list is never null, and has one element for each field in the row type. Each
* element is a list of four elements (catalog, schema, table, column), or may be null if the
* column is an expression.
*
* @param sqlQuery Query
* @return Description of how each field in the row type maps to a schema object
*/
List<List<String>> getFieldOrigins(SqlNode sqlQuery);
/**
* Returns a record type that contains the name and type of each parameter. Returns a record type
* with no fields if there are no parameters.
*
* @param sqlQuery Query
* @return Record type
*/
RelDataType getParameterRowType(SqlNode sqlQuery);
/**
* Returns the scope of an OVER or VALUES node.
*
* @param node Node
* @return Scope
*/
SqlValidatorScope getOverScope(SqlNode node);
/**
* Validates that a query is capable of producing a return of given modality (relational or
* streaming).
*
* @param select Query
* @param modality Modality (streaming or relational)
* @param fail Whether to throw a user error if does not support required modality
* @return whether query supports the given modality
*/
boolean validateModality(SqlSelect select, SqlModality modality, boolean fail);
void validateWith(SqlWith with, SqlValidatorScope scope);
void validateWithItem(SqlWithItem withItem);
void validateSequenceValue(SqlValidatorScope scope, SqlIdentifier id);
SqlValidatorScope getWithScope(SqlNode withItem);
}
/**
* Created by amognm on 11/18/15.
*
* <p>Utility function for Planners RuleSet
*/
public class RuleSets {
private RuleSets() {}
public static final boolean COMMUTE = Util.getBooleanProperty("calcite.enable.join.commute");
private static final ImmutableList<RelOptRule> DEFAULT_RULES =
ImmutableList.of(
AggStarRule.INSTANCE,
AggStarRule.INSTANCE2,
TableScanRule.INSTANCE,
COMMUTE ? JoinAssociateRule.INSTANCE : ProjectMergeRule.INSTANCE,
FilterTableScanRule.INSTANCE,
ProjectFilterTransposeRule.INSTANCE,
FilterProjectTransposeRule.INSTANCE,
FilterJoinRule.FILTER_ON_JOIN,
AggregateExpandDistinctAggregatesRule.INSTANCE,
AggregateReduceFunctionsRule.INSTANCE,
FilterAggregateTransposeRule.INSTANCE,
JoinCommuteRule.INSTANCE,
JoinPushThroughJoinRule.RIGHT,
JoinPushThroughJoinRule.LEFT,
SortProjectTransposeRule.INSTANCE);
private static final List<RelOptRule> ENUMERABLE_RULES =
ImmutableList.of(
EnumerableRules.ENUMERABLE_JOIN_RULE,
EnumerableRules.ENUMERABLE_MERGE_JOIN_RULE,
EnumerableRules.ENUMERABLE_SEMI_JOIN_RULE,
EnumerableRules.ENUMERABLE_CORRELATE_RULE,
EnumerableRules.ENUMERABLE_PROJECT_RULE,
EnumerableRules.ENUMERABLE_FILTER_RULE,
EnumerableRules.ENUMERABLE_AGGREGATE_RULE,
EnumerableRules.ENUMERABLE_SORT_RULE,
EnumerableRules.ENUMERABLE_LIMIT_RULE,
EnumerableRules.ENUMERABLE_COLLECT_RULE,
EnumerableRules.ENUMERABLE_UNCOLLECT_RULE,
EnumerableRules.ENUMERABLE_UNION_RULE,
EnumerableRules.ENUMERABLE_INTERSECT_RULE,
EnumerableRules.ENUMERABLE_MINUS_RULE,
EnumerableRules.ENUMERABLE_TABLE_MODIFICATION_RULE,
EnumerableRules.ENUMERABLE_VALUES_RULE,
EnumerableRules.ENUMERABLE_WINDOW_RULE,
EnumerableRules.ENUMERABLE_TABLE_SCAN_RULE,
EnumerableRules.ENUMERABLE_TABLE_FUNCTION_SCAN_RULE);
/** Gets the default set of rules for planning process */
public static RuleSet getDefaultRuleSet() {
ImmutableList.Builder<RelOptRule> builder = ImmutableList.builder();
builder.addAll(DEFAULT_RULES).addAll(ENUMERABLE_RULES);
return new QuarkRuleSet(builder.build());
}
/** Quark's Rule Set which will be used for planning process */
private static class QuarkRuleSet implements RuleSet {
final ImmutableList<RelOptRule> rules;
QuarkRuleSet(ImmutableList<RelOptRule> rules) {
this.rules = rules;
}
@Override
public Iterator<RelOptRule> iterator() {
return rules.iterator();
}
}
}
