/**
* Miscellaneous post parse activity .
*
* @param sql
* @param db
* @param joinOrder
*/
@Override
void postParse(String sql, String joinOrder) {
for (AbstractParsedStmt selectStmt : m_children) {
selectStmt.postParse(sql, joinOrder);
}
// these just shouldn't happen right?
assert (noTableSelectionList.size() == 0);
this.sql = sql;
this.joinOrder = joinOrder;
}
@Override
void parse(VoltXMLElement stmtNode) {
String type = stmtNode.attributes.get("uniontype");
// Set operation type
m_unionType = UnionType.valueOf(type);
assert (stmtNode.children.size() == m_children.size());
int i = 0;
for (VoltXMLElement selectSQL : stmtNode.children) {
AbstractParsedStmt nextSelectStmt = m_children.get(i++);
nextSelectStmt.parse(selectSQL);
}
}
/**
* Parse tables and parameters
*
* @param root
* @param db
*/
@Override
void parseTablesAndParams(VoltXMLElement stmtNode) {
assert (stmtNode.children.size() > 1);
tableList.clear();
for (VoltXMLElement childSQL : stmtNode.children) {
if (childSQL.name.equalsIgnoreCase(SELECT_NODE_NAME)) {
AbstractParsedStmt childStmt = new ParsedSelectStmt(this.m_paramValues, this.m_db);
childStmt.parseTablesAndParams(childSQL);
m_children.add(childStmt);
// So far T UNION T (as well as T JOIN T) are not handled properly
// by the fragmentizer. Need to give an error if any table is mentioned
// in the UNION TREE more than once.
if (childStmt.scanColumns != null) {
for (Table table : childStmt.tableList) {
String tableName = table.getTypeName();
if (m_uniqueTables.contains(tableName)) {
// The table is not 'unique' across the union
throw new PlanningErrorException(
"Table " + tableName + " appears more than once in the union statement");
} else {
m_uniqueTables.add(tableName);
}
}
} else {
throw new PlanningErrorException("Scan columns are NULL the UNION statement");
}
// Add statement's tables to the consolidated list
tableList.addAll(childStmt.tableList);
} else if (childSQL.name.equalsIgnoreCase(UNION_NODE_NAME)) {
ParsedUnionStmt childStmt = new ParsedUnionStmt(this.m_paramValues, this.m_db);
// Pass already accumulated unique tables to the child union
childStmt.m_uniqueTables = m_uniqueTables;
childStmt.parseTablesAndParams(childSQL);
m_children.add(childStmt);
// Add statement's tables to the consolidated list
tableList.addAll(childStmt.tableList);
// Child's unique tables now contains the consolidated list
m_uniqueTables = childStmt.m_uniqueTables;
} else {
throw new PlanningErrorException("Unexpected Element in UNION statement: " + childSQL.name);
}
}
}
/**
* @param sql
* @param xmlSQL
* @param db
*/
public static AbstractParsedStmt parse(
String sql,
VoltXMLElement stmtTypeElement,
String[] paramValues,
Database db,
String joinOrder) {
AbstractParsedStmt retval = null;
if (stmtTypeElement == null) {
System.err.println("Unexpected error parsing hsql parsed stmt xml");
throw new RuntimeException("Unexpected error parsing hsql parsed stmt xml");
}
// create non-abstract instances
if (stmtTypeElement.name.equalsIgnoreCase(INSERT_NODE_NAME)) {
retval = new ParsedInsertStmt(paramValues, db);
} else if (stmtTypeElement.name.equalsIgnoreCase(UPDATE_NODE_NAME)) {
retval = new ParsedUpdateStmt(paramValues, db);
} else if (stmtTypeElement.name.equalsIgnoreCase(DELETE_NODE_NAME)) {
retval = new ParsedDeleteStmt(paramValues, db);
} else if (stmtTypeElement.name.equalsIgnoreCase(SELECT_NODE_NAME)) {
retval = new ParsedSelectStmt(paramValues, db);
} else if (stmtTypeElement.name.equalsIgnoreCase(UNION_NODE_NAME)) {
retval = new ParsedUnionStmt(paramValues, db);
} else {
throw new RuntimeException("Unexpected Element: " + stmtTypeElement.name);
}
// parse tables and parameters
retval.parseTablesAndParams(stmtTypeElement);
// parse specifics
retval.parse(stmtTypeElement);
// post parse action
retval.postParse(sql, joinOrder);
return retval;
}
private CompiledPlan compileFromXML(VoltXMLElement xmlSQL, String[] paramValues) {
// Get a parsed statement from the xml
// The callers of compilePlan are ready to catch any exceptions thrown here.
AbstractParsedStmt parsedStmt =
AbstractParsedStmt.parse(m_sql, xmlSQL, paramValues, m_db, m_joinOrder);
if (parsedStmt == null) {
m_recentErrorMsg = "Failed to parse SQL statement: " + getOriginalSql();
return null;
}
if (m_isUpsert) {
// no insert/upsert with joins
if (parsedStmt.m_tableList.size() != 1) {
m_recentErrorMsg = "UPSERT is support only with one single table: " + getOriginalSql();
return null;
}
Table tb = parsedStmt.m_tableList.get(0);
Constraint pkey = null;
for (Constraint ct : tb.getConstraints()) {
if (ct.getType() == ConstraintType.PRIMARY_KEY.getValue()) {
pkey = ct;
break;
}
}
if (pkey == null) {
m_recentErrorMsg = "Unsupported UPSERT table without primary key: " + getOriginalSql();
return null;
}
}
m_planSelector.outputParsedStatement(parsedStmt);
// Init Assembler. Each plan assembler requires a new instance of the PlanSelector
// to keep track of the best plan
PlanAssembler assembler =
new PlanAssembler(m_cluster, m_db, m_partitioning, (PlanSelector) m_planSelector.clone());
// find the plan with minimal cost
CompiledPlan bestPlan = assembler.getBestCostPlan(parsedStmt);
// This processing of bestPlan outside/after getBestCostPlan
// allows getBestCostPlan to be called both here and
// in PlanAssembler.getNextUnion on each branch of a union.
// make sure we got a winner
if (bestPlan == null) {
if (m_debuggingStaticModeToRetryOnError) {
assembler.getBestCostPlan(parsedStmt);
}
m_recentErrorMsg = assembler.getErrorMessage();
if (m_recentErrorMsg == null) {
m_recentErrorMsg = "Unable to plan for statement. Error unknown.";
}
return null;
}
if (bestPlan.isReadOnly()) {
SendPlanNode sendNode = new SendPlanNode();
// connect the nodes to build the graph
sendNode.addAndLinkChild(bestPlan.rootPlanGraph);
// this plan is final, generate schema and resolve all the column index references
bestPlan.rootPlanGraph = sendNode;
}
// Execute the generateOutputSchema and resolveColumnIndexes once for the best plan
bestPlan.rootPlanGraph.generateOutputSchema(m_db);
bestPlan.rootPlanGraph.resolveColumnIndexes();
if (parsedStmt instanceof ParsedSelectStmt) {
List<SchemaColumn> columns = bestPlan.rootPlanGraph.getOutputSchema().getColumns();
((ParsedSelectStmt) parsedStmt).checkPlanColumnMatch(columns);
}
// Output the best plan debug info
assembler.finalizeBestCostPlan();
// reset all the plan node ids for a given plan
// this makes the ids deterministic
bestPlan.resetPlanNodeIds(1);
// split up the plan everywhere we see send/recieve into multiple plan fragments
List<AbstractPlanNode> receives =
bestPlan.rootPlanGraph.findAllNodesOfClass(AbstractReceivePlanNode.class);
if (receives.size() > 1) {
// Have too many receive node for two fragment plan limit
m_recentErrorMsg =
"This join of multiple partitioned tables is too complex. "
+ "Consider simplifying its subqueries: "
+ getOriginalSql();
return null;
}
/*/ enable for debug ...
if (receives.size() > 1) {
System.out.println(plan.rootPlanGraph.toExplainPlanString());
}
// ... enable for debug */
if (receives.size() == 1) {
AbstractReceivePlanNode recvNode = (AbstractReceivePlanNode) receives.get(0);
fragmentize(bestPlan, recvNode);
}
return bestPlan;
}