/* This file is part of VoltDB.
* Copyright (C) 2008-2017 VoltDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with VoltDB. If not, see <http://www.gnu.org/licenses/>.
*/
package org.voltdb.expressions;
import org.json_voltpatches.JSONException;
import org.json_voltpatches.JSONObject;
import org.json_voltpatches.JSONStringer;
import org.voltdb.VoltType;
import org.voltdb.catalog.Column;
import org.voltdb.catalog.Table;
import org.voltdb.planner.parseinfo.StmtTableScan;
import org.voltdb.plannodes.NodeSchema;
import org.voltdb.plannodes.SchemaColumn;
import org.voltdb.types.ExpressionType;
/**
*
*/
public class TupleValueExpression extends AbstractValueExpression {
private static class Members {
static final String COLUMN_IDX = "COLUMN_IDX";
// used for JOIN queries only, 0 for outer table, 1 for inner table
static final String TABLE_IDX = "TABLE_IDX";
}
private int m_columnIndex = -1;
private String m_tableName = null;
private String m_tableAlias = null;
private String m_columnName = null;
private String m_columnAlias = null;
private int m_tableIdx = 0;
// Tables that are not persistent tables, but those produced internally,
// (by subqueries for example) may contains columns whose names are the same.
// Consider this statement for example:
// SELECT * FROM (SELECT * FROM T, T) as sub_t;
// If the table T has a column named "C", then the output of the subquery will
// have two columns named "C". HSQL is able to tell these apart, so we use the
// "index" field produced by voltXML as a differentiator between identical columns.
private int m_differentiator = -1;
private boolean m_needsDifferentiation = true;
private boolean m_hasAggregate = false;
/** The statement id this TVE refers to */
private int m_origStmtId = -1;
/**
* Create a new TupleValueExpression
* @param tableName The name of the table where this column originated,
* if any. Currently, internally created columns will be assigned
* the table name AbstractParsedStmt.TEMP_TABLE_NAME for disambiguation.
* @param tableAlias The alias assigned to this table, if any
* @param columnName The name of this column, if any
* @param columnAlias The alias assigned to this column, if any
* @param columnIndex. The column index in the table
*/
public TupleValueExpression(String tableName,
String tableAlias,
String columnName,
String columnAlias,
int columnIndex,
int differentiator) {
super(ExpressionType.VALUE_TUPLE);
m_tableName = tableName;
m_tableAlias = tableAlias;
m_columnName = columnName;
m_columnAlias = columnAlias;
m_columnIndex = columnIndex;
m_differentiator = differentiator;
}
public TupleValueExpression(String tableName,
String tableAlias,
Column catalogCol,
int columnIndex) {
this(tableName, tableAlias,
catalogCol.getName(), catalogCol.getName(),
columnIndex, -1);
setTypeSizeAndInBytes(catalogCol);
}
public TupleValueExpression(String tableName,
String tableAlias,
String columnName,
String columnAlias,
int columnIndex) {
this(tableName, tableAlias, columnName, columnAlias, columnIndex, -1);
}
public TupleValueExpression(String tableName,
String tableAlias,
String columnName,
String columnAlias,
AbstractExpression typeSource,
int columnIndex) {
this(tableName, tableAlias, columnName, columnAlias, columnIndex, -1);
setTypeSizeAndInBytes(typeSource);
}
public TupleValueExpression(String tableName,
String tableAlias,
String columnName,
String columnAlias) {
this(tableName, tableAlias, columnName, columnAlias, -1, -1);
}
public TupleValueExpression(String tableName,
String columnName,
int columnIndex) {
this(tableName, null, columnName, null, columnIndex, -1);
}
public TupleValueExpression() {
super(ExpressionType.VALUE_TUPLE);
}
/*
* Only set for the special case of an aggregate function result used in
* an "ORDER BY" clause. This TupleValueExpression represents the
* corresponding "column" in the aggregate's generated output TEMP table.
*/
public boolean hasAggregate() {
return m_hasAggregate;
}
public void setHasAggregate(boolean hasAggregate) {
m_hasAggregate = hasAggregate;
}
@Override
public void validate() throws Exception {
super.validate();
if ((m_right != null) || (m_left != null))
throw new Exception(
"ERROR: A value expression has child expressions for '" +
this + "'");
// Column Index
if (m_columnIndex < 0) {
throw new Exception(
"ERROR: Invalid column index '" + m_columnIndex +
"' for '" + this + "'");
}
}
/**
* @return the column index
*/
public int getColumnIndex() {
return m_columnIndex;
}
/**
* @param columnIndex The index of the column to set
*/
public void setColumnIndex(int columnIndex) {
m_columnIndex = columnIndex;
}
/**
* @return the column_aliases
*/
public String getColumnAlias() {
return m_columnAlias;
}
/**
* @param columnAlias the column_alias to set
*/
public void setColumnAlias(String columnAlias) {
m_columnAlias = columnAlias;
}
/**
* @return the columns
*/
public String getColumnName() {
return m_columnName;
}
/**
* @param name the column name to set
*/
public void setColumnName(String name) {
m_columnName = name;
}
/**
* @return the table name for this column reference
*/
public String getTableName() {
return m_tableName;
}
/**
* @param name the table name to set
*/
public void setTableName(String name) {
m_tableName = name;
}
/**
* @return the table alias for this column reference
*/
public String getTableAlias() {
return m_tableAlias;
}
public void setTableAlias(String alias) {
m_tableAlias = alias;
}
boolean matchesTableAlias(String tableAlias) {
if (m_tableAlias == null) {
return m_tableName.equals(tableAlias);
}
return m_tableAlias.equals(tableAlias);
}
public int getTableIndex() {
return m_tableIdx;
}
public void setTableIndex(int idx) {
m_tableIdx = idx;
}
/**
* Get the differentiator field (a number used to make this field distinct
* from other column with the same name with a table schema).
*/
public int getDifferentiator() {
return m_differentiator;
}
/**
* Set the differentiator field (a number used to make this field distinct
* from other column with the same name with a table schema).
*/
public void setDifferentiator(int val) {
m_differentiator = val;
}
public final boolean needsDifferentiation() {
return m_needsDifferentiation;
}
public final void setNeedsNoDifferentiation() {
m_needsDifferentiation = false;
}
/**
* Set the parent TVE indicator
* @param parentTve
*/
public void setOrigStmtId(int origStmtId) {
m_origStmtId = origStmtId;
}
/**
* @return parent TVE indicator
*/
public int getOrigStmtId() {
return m_origStmtId;
}
public void setTypeSizeAndInBytes(AbstractExpression typeSource) {
setValueType(typeSource.getValueType());
setValueSize(typeSource.getValueSize());
m_inBytes = typeSource.getInBytes();
}
public void setTypeSizeAndInBytes(SchemaColumn typeSource) {
setValueType(typeSource.getType());
setValueSize(typeSource.getSize());
m_inBytes = typeSource.getExpression().getInBytes();
}
private void setTypeSizeAndInBytes(Column typeSource) {
setValueType(VoltType.get((byte)typeSource.getType()));
setValueSize(typeSource.getSize());
m_inBytes = typeSource.getInbytes();
}
@Override
public boolean equals(Object obj) {
if (obj instanceof TupleValueExpression == false) {
return false;
}
TupleValueExpression expr = (TupleValueExpression) obj;
if (m_origStmtId != -1 && expr.m_origStmtId != -1) {
// Implying both sides have statement id set
// If one of the ids is not set it is considered to be a wild card
// matching any other id.
if (m_origStmtId != expr.m_origStmtId) {
return false;
}
}
if ((m_tableName == null) != (expr.m_tableName == null)) {
return false;
}
if ((m_columnName == null) != (expr.m_columnName == null)) {
return false;
}
if (m_tableName != null) { // Implying both sides non-null
if (m_tableName.equals(expr.m_tableName) == false) {
return false;
}
}
if (m_tableAlias != null && expr.m_tableAlias != null) {
// Implying both sides non-null
// If one of the table aliases is NULL it is considered to be a wild card
// matching any alias.
if (m_tableAlias.equals(expr.m_tableAlias) == false) {
return false;
}
}
if (m_columnName != null) { // Implying both sides non-null
if (m_columnName.equals(expr.m_columnName) == false) {
return false;
}
}
return true;
}
@Override
public int hashCode() {
// based on implementation of equals
int result = 0;
if (m_tableName != null) {
result += m_tableName.hashCode();
}
if (m_columnName != null) {
result += m_columnName.hashCode();
}
// defer to the superclass, which factors in other attributes
return result += super.hashCode();
}
@Override
public void toJSONString(JSONStringer stringer) throws JSONException {
super.toJSONString(stringer);
stringer.keySymbolValuePair(Members.COLUMN_IDX, m_columnIndex);
if (m_tableIdx > 0) {
stringer.keySymbolValuePair(Members.TABLE_IDX, m_tableIdx);
}
}
@Override
protected void loadFromJSONObject(JSONObject obj, StmtTableScan tableScan)
throws JSONException {
m_columnIndex = obj.getInt(Members.COLUMN_IDX);
if (obj.has(Members.TABLE_IDX)) {
m_tableIdx = obj.getInt(Members.TABLE_IDX);
}
if (tableScan != null) {
m_tableAlias = tableScan.getTableAlias();
m_tableName = tableScan.getTableName();
m_columnName = tableScan.getColumnName(m_columnIndex);
}
}
@Override
public void resolveForTable(Table table) {
assert(table != null);
// It MAY be that for the case in which this function is called (expression indexes), the column's
// table name is not specified (and not missed?).
// It is possible to "correct" that here by cribbing it from the supplied table (base table for the index)
// -- not bothering for now.
Column column = table.getColumns().getExact(m_columnName);
assert(column != null);
m_tableName = table.getTypeName();
m_columnIndex = column.getIndex();
setTypeSizeAndInBytes(column);
}
/**
* Given an input schema, resolve this TVE expression.
*/
public int setColumnIndexUsingSchema(NodeSchema inputSchema) {
int index = inputSchema.getIndexOfTve(this);
if (index < 0) {
//* enable to debug*/ System.out.println("DEBUG: setColumnIndex miss: " + this);
//* enable to debug*/ System.out.println("DEBUG: setColumnIndex candidates: " + inputSchema);
return index;
}
setColumnIndex(index);
if (getValueType() == null) {
// In case of sub-queries the TVE may not have its
// value type and size resolved yet. Try to resolve it now
SchemaColumn inputColumn = inputSchema.getColumns().get(index);
setTypeSizeAndInBytes(inputColumn);
}
return index;
}
// Even though this function applies generally to expressions and tables
// and not just to TVEs as such, it is somewhat TVE-related because TVEs
// represent the points where expression trees depend on tables.
public static AbstractExpression getOtherTableExpression(
AbstractExpression expr, String tableAlias) {
assert(expr != null);
AbstractExpression retval = expr.getLeft();
if (isOperandDependentOnTable(retval, tableAlias)) {
retval = expr.getRight();
assert( ! isOperandDependentOnTable(retval, tableAlias));
}
return retval;
}
// Even though this function applies generally to expressions and tables
// and not just to TVEs as such, it is somewhat TVE-related because TVEs
// represent the points where expression trees depend on tables.
public static boolean isOperandDependentOnTable(AbstractExpression expr,
String tableAlias) {
assert(tableAlias != null);
for (TupleValueExpression tve :
ExpressionUtil.getTupleValueExpressions(expr)) {
if (tableAlias.equals(tve.getTableAlias())) {
return true;
}
}
return false;
}
@Override
public String explain(String impliedTableName) {
String tableName = (m_tableAlias != null) ? m_tableAlias : m_tableName;
String columnName = m_columnName;
if (columnName == null || columnName.equals("")) {
columnName = "column#" + m_columnIndex;
}
if (m_verboseExplainForDebugging) {
columnName += " (as JSON: ";
JSONStringer stringer = new JSONStringer();
try {
stringer.object();
toJSONString(stringer);
stringer.endObject();
columnName += stringer.toString();
}
catch (Exception e) {
columnName += "CORRUPTED beyond the ability to format? " + e;
e.printStackTrace();
}
columnName += ")";
}
if (tableName == null) {
if (m_tableIdx != 0) {
assert(m_tableIdx == 1);
// This is join inner table
return "inner-table." + columnName;
}
}
else if ( ! tableName.equals(impliedTableName)) {
return tableName + "." + columnName;
}
else if (m_verboseExplainForDebugging) {
// In verbose mode, always show an "implied' tableName that would normally be left off.
return "{" + tableName + "}." + columnName;
}
return columnName;
}
private String chooseFromTwoNames(String name, String alias) {
if (name == null) {
if (alias == null) {
return "<none>";
}
return "(" + alias + ")";
}
if (alias == null || name.equals(alias)) {
return name;
}
return name + "(" + alias + ")";
}
@Override
protected String getExpressionNodeNameForToString() {
return String.format("%s: %s.%s(index:%d, diff'tor:%d)",
super.getExpressionNodeNameForToString(),
chooseFromTwoNames(m_tableName, m_tableAlias),
chooseFromTwoNames(m_columnName, m_columnAlias),
m_columnIndex, m_differentiator);
}
}