001 /*
002 // $Id: //open/mondrian/src/main/mondrian/rolap/agg/DrillThroughQuerySpec.java#14 $
003 // This software is subject to the terms of the Common Public License
004 // Agreement, available at the following URL:
005 // http://www.opensource.org/licenses/cpl.html.
006 // Copyright (C) 2005-2008 Julian Hyde
007 // All Rights Reserved.
008 // You must accept the terms of that agreement to use this software.
009 */
010
011 package mondrian.rolap.agg;
012
013 import mondrian.olap.Util;
014 import mondrian.olap.MondrianDef;
015 import mondrian.rolap.RolapStar;
016 import mondrian.rolap.StarColumnPredicate;
017 import mondrian.rolap.sql.SqlQuery;
018 import java.util.ArrayList;
019 import java.util.List;
020 import java.util.HashSet;
021 import java.util.Set;
022
023 /**
024 * Provides the information necessary to generate SQL for a drill-through
025 * request.
026 *
027 * @author jhyde
028 * @author Richard M. Emberson
029 * @version $Id: //open/mondrian/src/main/mondrian/rolap/agg/DrillThroughQuerySpec.java#14 $
030 */
031 class DrillThroughQuerySpec extends AbstractQuerySpec {
032 private final CellRequest request;
033 private final List<String> columnNames;
034 private final int maxColumnNameLength;
035
036 public DrillThroughQuerySpec(CellRequest request, boolean countOnly) {
037 super(request.getMeasure().getStar(), countOnly);
038 this.request = request;
039 int tmpMaxColumnNameLength =
040 getStar().getSqlQueryDialect().getMaxColumnNameLength();
041 if (tmpMaxColumnNameLength == 0) {
042 // From java.sql.DatabaseMetaData: "a result of zero means that
043 // there is no limit or the limit is not known"
044 maxColumnNameLength = Integer.MAX_VALUE;
045 } else {
046 maxColumnNameLength = tmpMaxColumnNameLength;
047 }
048 this.columnNames = computeDistinctColumnNames();
049 }
050
051 private List<String> computeDistinctColumnNames() {
052 final List<String> columnNames = new ArrayList<String>();
053 final Set<String> columnNameSet = new HashSet<String>();
054
055 final RolapStar.Column[] columns = getColumns();
056 for (RolapStar.Column column : columns) {
057 addColumnName(column, columnNames, columnNameSet);
058 }
059
060 addColumnName(request.getMeasure(), columnNames, columnNameSet);
061
062 return columnNames;
063 }
064
065 private void addColumnName(
066 final RolapStar.Column column,
067 final List<String> columnNames,
068 final Set<String> columnNameSet)
069 {
070 String columnName = column.getName();
071 if (columnName != null) {
072 // nothing
073 } else if (column.getExpression() instanceof MondrianDef.Column) {
074 columnName = ((MondrianDef.Column) column.getExpression()).name;
075 } else {
076 columnName = "c" + Integer.toString(columnNames.size());
077 }
078 // Register the column name, and if it's not unique, append numeric
079 // suffixes until it is. Also make sure that it is within the
080 // range allowed by this SQL dialect.
081 String originalColumnName = columnName;
082 if (columnName.length() > maxColumnNameLength) {
083 columnName = columnName.substring(0, maxColumnNameLength);
084 }
085 for (int j = 0; !columnNameSet.add(columnName); j++) {
086 final String suffix = "_" + Integer.toString(j);
087 columnName = originalColumnName;
088 if (originalColumnName.length() + suffix.length()
089 > maxColumnNameLength) {
090 columnName =
091 originalColumnName.substring(
092 0, maxColumnNameLength - suffix.length());
093 }
094 columnName += suffix;
095 }
096 columnNames.add(columnName);
097 }
098
099 public int getMeasureCount() {
100 return 1;
101 }
102
103 public RolapStar.Measure getMeasure(final int i) {
104 Util.assertTrue(i == 0);
105 return request.getMeasure();
106 }
107
108 public String getMeasureAlias(final int i) {
109 Util.assertTrue(i == 0);
110 return columnNames.get(columnNames.size() - 1);
111 }
112
113 public RolapStar.Column[] getColumns() {
114 return request.getConstrainedColumns();
115 }
116
117 public String getColumnAlias(final int i) {
118 return columnNames.get(i);
119 }
120
121 public StarColumnPredicate getColumnPredicate(final int i) {
122 final StarColumnPredicate constr = request.getValueList().get(i);
123 return (constr == null)
124 ? LiteralStarPredicate.TRUE
125 : constr;
126 }
127
128 public String generateSqlQuery() {
129 SqlQuery sqlQuery = newSqlQuery();
130 nonDistinctGenerateSql(sqlQuery);
131 return sqlQuery.toString();
132 }
133
134 protected void addMeasure(final int i, final SqlQuery sqlQuery) {
135 RolapStar.Measure measure = getMeasure(i);
136
137 Util.assertTrue(measure.getTable() == getStar().getFactTable());
138 measure.getTable().addToFrom(sqlQuery, false, true);
139
140 String expr = measure.generateExprString(sqlQuery);
141 sqlQuery.addSelect(expr, getMeasureAlias(i));
142 }
143
144 protected boolean isAggregate() {
145 return false;
146 }
147
148 protected boolean isOrdered() {
149 return true;
150 }
151 }
152
153 // End DrillThroughQuerySpec.java