public void execQueryOnVirtualTable(
QueryContext queryContext,
Session session,
String query,
LogicalPlan plan,
SubmitQueryResponse.Builder response)
throws Exception {
int maxRow = Integer.MAX_VALUE;
if (plan.getRootBlock().hasNode(NodeType.LIMIT)) {
LimitNode limitNode = plan.getRootBlock().getNode(NodeType.LIMIT);
maxRow = (int) limitNode.getFetchFirstNum();
}
QueryInfo queryInfo =
context
.getQueryJobManager()
.createNewSimpleQuery(
queryContext, session, query, (LogicalRootNode) plan.getRootBlock().getRoot());
NonForwardQueryResultScanner queryResultScanner =
new NonForwardQueryResultSystemScanner(
context, plan, queryInfo.getQueryId(), session.getSessionId(), maxRow);
queryResultScanner.init();
session.addNonForwardQueryResultScanner(queryResultScanner);
response.setState(OK);
response.setQueryId(queryInfo.getQueryId().getProto());
response.setResultType(ResultType.ENCLOSED);
response.setMaxRowNum(maxRow);
response.setTableDesc(queryResultScanner.getTableDesc().getProto());
}
public void execSetSession(
Session session, LogicalPlan plan, SubmitQueryResponse.Builder response) {
SetSessionNode setSessionNode = ((LogicalRootNode) plan.getRootBlock().getRoot()).getChild();
final String varName = setSessionNode.getName();
// SET CATALOG 'XXX'
if (varName.equals(SessionVars.CURRENT_DATABASE.name())) {
String databaseName = setSessionNode.getValue();
if (catalog.existDatabase(databaseName)) {
session.selectDatabase(setSessionNode.getValue());
} else {
response.setQueryId(QueryIdFactory.NULL_QUERY_ID.getProto());
response.setState(errUndefinedDatabase(databaseName));
}
// others
} else {
if (setSessionNode.hasValue()) {
session.setVariable(varName, setSessionNode.getValue());
} else {
session.removeVariable(varName);
}
}
response.setQueryId(QueryIdFactory.NULL_QUERY_ID.getProto());
response.setState(OK);
}
public void execSimpleQuery(
QueryContext queryContext,
Session session,
String query,
LogicalPlan plan,
SubmitQueryResponse.Builder response)
throws Exception {
ScanNode scanNode = plan.getRootBlock().getNode(NodeType.SCAN);
TableDesc desc = scanNode.getTableDesc();
if (desc.hasPartition()) {
scanNode = plan.getRootBlock().getNode(NodeType.PARTITIONS_SCAN);
}
int maxRow = Integer.MAX_VALUE;
if (plan.getRootBlock().hasNode(NodeType.LIMIT)) {
LimitNode limitNode = plan.getRootBlock().getNode(NodeType.LIMIT);
maxRow = (int) limitNode.getFetchFirstNum();
}
if (desc.getStats().getNumRows() == 0) {
desc.getStats().setNumRows(TajoConstants.UNKNOWN_ROW_NUMBER);
}
QueryInfo queryInfo =
context
.getQueryJobManager()
.createNewSimpleQuery(
queryContext, session, query, (LogicalRootNode) plan.getRootBlock().getRoot());
NonForwardQueryResultScanner queryResultScanner =
new NonForwardQueryResultFileScanner(
context.getConf(),
session.getSessionId(),
queryInfo.getQueryId(),
scanNode,
desc,
maxRow);
queryResultScanner.init();
session.addNonForwardQueryResultScanner(queryResultScanner);
response.setState(OK);
response.setQueryId(queryInfo.getQueryId().getProto());
response.setResultType(ResultType.ENCLOSED);
response.setMaxRowNum(maxRow);
response.setTableDesc(desc.getProto());
}
public SubmitQueryResponse execute(
QueryContext queryContext, Session session, String sql, String jsonExpr, LogicalPlan plan)
throws Exception {
SubmitQueryResponse.Builder response = SubmitQueryResponse.newBuilder();
response.setUserName(queryContext.get(SessionVars.USERNAME));
LogicalRootNode rootNode = plan.getRootBlock().getRoot();
if (PlannerUtil.checkIfSetSession(rootNode)) {
execSetSession(session, plan, response);
} else if (PlannerUtil.checkIfDDLPlan(rootNode)) {
if (PlannerUtil.isDistExecDDL(rootNode)) {
if (rootNode.getChild().getType() == NodeType.CREATE_INDEX) {
checkIndexExistence(queryContext, (CreateIndexNode) rootNode.getChild());
}
executeDistributedQuery(queryContext, session, plan, sql, jsonExpr, response);
} else {
ddlExecutor.execute(queryContext, plan);
response.setState(OK);
response.setResultType(ResultType.NO_RESULT);
}
} else if (plan.isExplain()) { // explain query
execExplain(session, sql, plan, queryContext, plan.isExplainGlobal(), response);
} else if (PlannerUtil.checkIfQueryTargetIsVirtualTable(plan)) {
execQueryOnVirtualTable(queryContext, session, sql, plan, response);
// Simple query indicates a form of 'select * from tb_name [LIMIT X];'.
} else if (PlannerUtil.checkIfSimpleQuery(plan)) {
execSimpleQuery(queryContext, session, sql, plan, response);
// NonFromQuery indicates a form of 'select a, x+y;'
} else if (PlannerUtil.checkIfNonFromQuery(plan)) {
execNonFromQuery(queryContext, session, sql, plan, response);
} else { // it requires distributed execution. So, the query is forwarded to a query master.
executeDistributedQuery(queryContext, session, plan, sql, jsonExpr, response);
}
response.setSessionVars(ProtoUtil.convertFromMap(session.getAllVariables()));
return response.build();
}