package org.h2.expression.condition;
import org.h2.command.dml.Query;
import org.h2.engine.Session;
import org.h2.expression.Expression;
import org.h2.expression.ExpressionVisitor;
import org.h2.result.ResultInterface;
import org.h2.table.ColumnResolver;
import org.h2.table.TableFilter;
import org.h2.util.StringUtils;
import org.h2.value.Value;
import org.h2.value.ValueBoolean;
public class ConditionExists extends Condition {
private final Query query;
public ConditionExists(Query query) {
this.query = query;
}
@Override
public Value getValue(Session session) {
query.setSession(session);
ResultInterface result = query.query(1);
session.addTemporaryResult(result);
boolean r = result.hasNext();
return ValueBoolean.get(r);
}
@Override
public Expression optimize(Session session) {
session.optimizeQueryExpression(query);
return this;
}
@Override
public StringBuilder getSQL(StringBuilder builder, boolean alwaysQuote) {
builder.append("EXISTS(\n");
return StringUtils.indent(builder, query.getPlanSQL(alwaysQuote), 4, false).append(')');
}
@Override
public void updateAggregate(Session session, int stage) {
}
@Override
public void mapColumns(ColumnResolver resolver, int level, int state) {
query.mapColumns(resolver, level + 1);
}
@Override
public void setEvaluatable(TableFilter tableFilter, boolean b) {
query.setEvaluatable(tableFilter, b);
}
@Override
public boolean isEverything(ExpressionVisitor visitor) {
return query.isEverything(visitor);
}
@Override
public int getCost() {
return query.getCostAsExpression();
}
}