@Override
public void prepare() {
if (columns == null) {
// 如INSERT INTO InsertTest DEFAULT VALUES
if (list.size() > 0 && list.get(0).length == 0) {
// special case where table is used as a sequence
columns = new Column[0];
} else { // 如INSERT INTO InsertTest(SELECT * FROM tmpSelectTest)
columns = table.getColumns();
}
}
if (list.size() > 0) {
for (Expression[] expr : list) {
if (expr.length != columns.length) {
throw DbException.get(ErrorCode.COLUMN_COUNT_DOES_NOT_MATCH);
}
for (int i = 0, len = expr.length; i < len; i++) {
Expression e = expr[i];
if (e != null) {
e = e.optimize(session);
if (e instanceof Parameter) {
Parameter p = (Parameter) e;
p.setColumn(columns[i]);
}
expr[i] = e;
}
}
}
} else {
query.prepare();
if (query.getColumnCount() != columns.length) {
throw DbException.get(ErrorCode.COLUMN_COUNT_DOES_NOT_MATCH);
}
}
}
private void setParameters(Command command) throws IOException {
int len = transfer.readInt();
ArrayList<? extends ParameterInterface> params = command.getParameters();
for (int i = 0; i < len; i++) {
Parameter p = (Parameter) params.get(i);
p.setValue(transfer.readValue());
}
}
private void setParameter(ArrayList<Parameter> paramList, int x, Value v) {
if (x >= paramList.size()) {
// the parameter may be optimized away as in
// select * from (select null as x) where x=1;
return;
}
Parameter param = paramList.get(x);
param.setValue(v);
}
public Cursor find(Session session, SearchRow first, SearchRow last) {
if (recursive) {
if (view.getRecursiveResult() != null) {
ResultInterface r = view.getRecursiveResult();
r.reset();
return new ViewCursor(table, r);
}
if (query == null) {
query = (Query) createSession.prepare(querySQL, true);
planSQL = query.getPlanSQL();
}
if (!(query instanceof SelectUnion)) {
throw DbException.get(ErrorCode.SYNTAX_ERROR_2, "recursive queries without UNION ALL");
}
SelectUnion union = (SelectUnion) query;
if (union.getUnionType() != SelectUnion.UNION_ALL) {
throw DbException.get(ErrorCode.SYNTAX_ERROR_2, "recursive queries without UNION ALL");
}
Query left = union.getLeft();
ResultInterface r = left.query(0);
LocalResult result = union.getEmptyResult();
while (r.next()) {
result.addRow(r.currentRow());
}
Query right = union.getRight();
r.reset();
view.setRecursiveResult(r);
while (true) {
r = right.query(0);
if (r.getRowCount() == 0) {
break;
}
while (r.next()) {
result.addRow(r.currentRow());
}
r.reset();
view.setRecursiveResult(r);
}
return new ViewCursor(table, result);
}
ArrayList<Parameter> paramList = query.getParameters();
for (int i = 0; originalParameters != null && i < originalParameters.size(); i++) {
Parameter orig = originalParameters.get(i);
int idx = orig.getIndex();
Value value = orig.getValue(session);
setParameter(paramList, idx, value);
}
int len;
if (first != null) {
len = first.getColumnCount();
} else if (last != null) {
len = last.getColumnCount();
} else {
len = 0;
}
int idx = originalParameters == null ? 0 : originalParameters.size();
idx += view.getParameterOffset();
for (int i = 0; i < len; i++) {
if (first != null) {
Value v = first.getValue(i);
if (v != null) {
int x = idx++;
setParameter(paramList, x, v);
}
}
// for equality, only one parameter is used (first == last)
if (last != null && indexMasks[i] != IndexCondition.EQUALITY) {
Value v = last.getValue(i);
if (v != null) {
int x = idx++;
setParameter(paramList, x, v);
}
}
}
ResultInterface result = query.query(0);
return new ViewCursor(table, result);
}