/**
* Get the best plan for the given search mask.
*
* @param session the session
* @param masks per-column comparison bit masks, null means 'always false', see constants in
* IndexCondition
* @param sortOrder the sort order
* @return the plan item
*/
public PlanItem getBestPlanItem(Session session, int[] masks, SortOrder sortOrder) {
PlanItem item = new PlanItem();
item.setIndex(getScanIndex(session));
item.cost = item.getIndex().getCost(session, null, null);
ArrayList<Index> indexes = getIndexes();
if (indexes != null && masks != null) {
for (int i = 1, size = indexes.size(); i < size; i++) {
Index index = indexes.get(i);
double cost = index.getCost(session, masks, sortOrder);
if (cost < item.cost) {
item.cost = cost;
item.setIndex(index);
}
}
}
return item;
}
public PlanItem getBestPlanItem(Session session, int[] masks) {
PlanItem item = new PlanItem();
item.cost = index.getCost(session, masks);
IntArray masksArray = new IntArray(masks == null ? Utils.EMPTY_INT_ARRAY : masks);
ViewIndex i2 = indexCache.get(masksArray);
if (i2 == null || i2.getSession() != session) {
i2 = new ViewIndex(this, index, session, masks);
indexCache.put(masksArray, i2);
}
item.setIndex(i2);
return item;
}
public PlanItem getBestPlanItem(Session session, int[] masks, TableFilter[] filters, int filter) {
PlanItem item = new PlanItem();
item.cost = Constants.COST_ROW_OFFSET;
if (tableRule instanceof ShardedTableRule) {
ShardedTableRule shardedTableRule = (ShardedTableRule) tableRule;
int nodeCount = shardedTableRule.getObjectNodes().length;
item.cost = Constants.COST_ROW_OFFSET * nodeCount;
}
Column[] columns = getRuleColumns();
if (columns != null && masks != null) {
for (int i = 0, len = columns.length; i < len; i++) {
Column column = columns[i];
int index = column.getColumnId();
int mask = masks[index];
if ((mask & IndexCondition.EQUALITY) == IndexCondition.EQUALITY) {
if (i == columns.length - 1) {
item.cost = Constants.COST_ROW_OFFSET;
item.scanningStrategyFor(ScanningStrategy.USE_SHARDINGKEY);
break;
}
} else {
break;
}
}
}
double rowsCost = item.cost;
ArrayList<Index> indexes = getIndexes();
if (indexes != null && masks != null) {
for (Index index : indexes) {
columns = index.getColumns();
for (int i = 0, len = columns.length; i < len; i++) {
Column column = columns[i];
int columnId = column.getColumnId();
int mask = masks[columnId];
if ((mask & IndexCondition.EQUALITY) == IndexCondition.EQUALITY) {
if (i == columns.length - 1 && index.getIndexType().isUnique()) {
item.cost = rowsCost * 0.25d;
item.scanningStrategyFor(ScanningStrategy.USE_UNIQUEKEY);
break;
}
item.cost = Math.max(rowsCost * 0.5d, item.cost * 0.5d);
item.scanningStrategyFor(ScanningStrategy.USE_INDEXKEY);
} else if ((mask & IndexCondition.RANGE) == IndexCondition.RANGE) {
item.cost = item.cost * 0.70d;
item.scanningStrategyFor(ScanningStrategy.USE_INDEXKEY);
break;
} else if ((mask & IndexCondition.START) == IndexCondition.START) {
item.cost = item.cost * 0.75d;
item.scanningStrategyFor(ScanningStrategy.USE_INDEXKEY);
break;
} else if ((mask & IndexCondition.END) == IndexCondition.END) {
item.cost = item.cost * 0.75d;
item.scanningStrategyFor(ScanningStrategy.USE_INDEXKEY);
break;
} else {
break;
}
}
}
}
// validationPlanItem(item);
return item;
}
