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org.apache.hadoop.hive.ql.exec.ExplainTask Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hive.ql.exec;
import static org.apache.hadoop.hive.serde.serdeConstants.STRING_TYPE_NAME;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.TreeMap;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hive.metastore.api.FieldSchema;
import org.apache.hadoop.hive.ql.Driver;
import org.apache.hadoop.hive.ql.DriverContext;
import org.apache.hadoop.hive.ql.hooks.ReadEntity;
import org.apache.hadoop.hive.ql.metadata.Table;
import org.apache.hadoop.hive.ql.optimizer.physical.StageIDsRearranger;
import org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer;
import org.apache.hadoop.hive.ql.plan.Explain;
import org.apache.hadoop.hive.ql.plan.ExplainWork;
import org.apache.hadoop.hive.ql.plan.HiveOperation;
import org.apache.hadoop.hive.ql.plan.OperatorDesc;
import org.apache.hadoop.hive.ql.plan.TezWork;
import org.apache.hadoop.hive.ql.plan.api.StageType;
import org.apache.hadoop.hive.ql.security.authorization.AuthorizationFactory;
import org.apache.hadoop.hive.ql.session.SessionState;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.util.StringUtils;
import org.apache.hive.common.util.AnnotationUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
/**
* ExplainTask implementation.
*
**/
public class ExplainTask extends Task implements Serializable {
private static final long serialVersionUID = 1L;
public static final String EXPL_COLUMN_NAME = "Explain";
private final Set> visitedOps = new HashSet>();
private boolean isLogical = false;
public ExplainTask() {
super();
}
/*
* Below method returns the dependencies for the passed in query to EXPLAIN.
* The dependencies are the set of input tables and partitions, and are
* provided back as JSON output for the EXPLAIN command.
* Example output:
* {"input_tables":[{"tablename": "default@test_sambavi_v1", "tabletype": "TABLE"}],
* "input partitions":["default@srcpart@ds=2008-04-08/hr=11"]}
*/
private static JSONObject getJSONDependencies(ExplainWork work)
throws Exception {
assert(work.getDependency());
JSONObject outJSONObject = new JSONObject();
List> inputTableInfo = new ArrayList>();
List> inputPartitionInfo = new ArrayList>();
for (ReadEntity input: work.getInputs()) {
switch (input.getType()) {
case TABLE:
Table table = input.getTable();
Map tableInfo = new HashMap();
tableInfo.put("tablename", table.getCompleteName());
tableInfo.put("tabletype", table.getTableType().toString());
if ((input.getParents() != null) && (!input.getParents().isEmpty())) {
tableInfo.put("tableParents", input.getParents().toString());
}
inputTableInfo.add(tableInfo);
break;
case PARTITION:
Map partitionInfo = new HashMap();
partitionInfo.put("partitionName", input.getPartition().getCompleteName());
if ((input.getParents() != null) && (!input.getParents().isEmpty())) {
partitionInfo.put("partitionParents", input.getParents().toString());
}
inputPartitionInfo.add(partitionInfo);
break;
default:
break;
}
}
outJSONObject.put("input_tables", inputTableInfo);
outJSONObject.put("input_partitions", inputPartitionInfo);
return outJSONObject;
}
public JSONObject getJSONLogicalPlan(PrintStream out, ExplainWork work) throws Exception {
isLogical = true;
JSONObject outJSONObject = new JSONObject();
boolean jsonOutput = work.isFormatted();
if (jsonOutput) {
out = null;
}
// Print out the parse AST
if (work.getAstStringTree() != null) {
String jsonAST = outputAST(work.getAstStringTree(), out, jsonOutput, 0);
if (out != null) {
out.println();
}
if (jsonOutput) {
outJSONObject.put("ABSTRACT SYNTAX TREE", jsonAST);
}
}
if (work.getParseContext() != null) {
if (out != null) {
out.print("LOGICAL PLAN:");
}
JSONObject jsonPlan = outputMap(work.getParseContext().getTopOps(), true,
out, jsonOutput, work.getExtended(), 0);
if (out != null) {
out.println();
}
if (jsonOutput) {
outJSONObject.put("LOGICAL PLAN", jsonPlan);
}
} else {
System.err.println("No parse context!");
}
return outJSONObject;
}
public JSONObject getJSONPlan(PrintStream out, ExplainWork work)
throws Exception {
return getJSONPlan(out, work.getAstStringTree(), work.getRootTasks(), work.getFetchTask(),
work.isFormatted(), work.getExtended(), work.isAppendTaskType());
}
public JSONObject getJSONPlan(PrintStream out, String ast, List> tasks, Task fetchTask,
boolean jsonOutput, boolean isExtended, boolean appendTaskType) throws Exception {
// If the user asked for a formatted output, dump the json output
// in the output stream
JSONObject outJSONObject = new JSONObject();
if (jsonOutput) {
out = null;
}
// Print out the parse AST
if (ast != null && isExtended) {
String jsonAST = outputAST(ast, out, jsonOutput, 0);
if (out != null) {
out.println();
}
if (jsonOutput) {
outJSONObject.put("ABSTRACT SYNTAX TREE", jsonAST);
}
}
List ordered = StageIDsRearranger.getExplainOrder(conf, tasks);
if (fetchTask != null) {
fetchTask.setParentTasks((List)StageIDsRearranger.getFetchSources(tasks));
if (fetchTask.getNumParent() == 0) {
fetchTask.setRootTask(true);
}
ordered.add(fetchTask);
}
JSONObject jsonDependencies = outputDependencies(out, jsonOutput, appendTaskType, ordered);
if (out != null) {
out.println();
}
if (jsonOutput) {
outJSONObject.put("STAGE DEPENDENCIES", jsonDependencies);
}
// Go over all the tasks and dump out the plans
JSONObject jsonPlan = outputStagePlans(out, ordered,
jsonOutput, isExtended);
if (jsonOutput) {
outJSONObject.put("STAGE PLANS", jsonPlan);
}
if (fetchTask != null) {
fetchTask.setParentTasks(null);
}
return jsonOutput ? outJSONObject : null;
}
private List toString(Collection objects) {
List list = new ArrayList();
for (Object object : objects) {
list.add(String.valueOf(object));
}
return list;
}
private Object toJson(String header, String message, PrintStream out, ExplainWork work)
throws Exception {
if (work.isFormatted()) {
return message;
}
out.print(header);
out.println(": ");
out.print(indentString(2));
out.println(message);
return null;
}
private Object toJson(String header, List messages, PrintStream out, ExplainWork work)
throws Exception {
if (work.isFormatted()) {
return new JSONArray(messages);
}
out.print(header);
out.println(": ");
for (String message : messages) {
out.print(indentString(2));
out.print(message);
out.println();
}
return null;
}
@Override
public int execute(DriverContext driverContext) {
PrintStream out = null;
try {
Path resFile = work.getResFile();
OutputStream outS = resFile.getFileSystem(conf).create(resFile);
out = new PrintStream(outS);
if (work.isLogical()) {
JSONObject jsonLogicalPlan = getJSONLogicalPlan(out, work);
if (work.isFormatted()) {
out.print(jsonLogicalPlan);
}
} else if (work.isAuthorize()) {
JSONObject jsonAuth = collectAuthRelatedEntities(out, work);
if (work.isFormatted()) {
out.print(jsonAuth);
}
} else if (work.getDependency()) {
JSONObject jsonDependencies = getJSONDependencies(work);
out.print(jsonDependencies);
} else {
if (work.getDependency()) {
JSONObject jsonDependencies = getJSONDependencies(work);
out.print(jsonDependencies);
} else {
JSONObject jsonPlan = getJSONPlan(out, work);
if (work.isFormatted()) {
out.print(jsonPlan);
}
}
}
out.close();
out = null;
return (0);
}
catch (Exception e) {
console.printError("Failed with exception " + e.getMessage(),
"\n" + StringUtils.stringifyException(e));
return (1);
}
finally {
IOUtils.closeStream(out);
}
}
private JSONObject collectAuthRelatedEntities(PrintStream out, ExplainWork work)
throws Exception {
BaseSemanticAnalyzer analyzer = work.getAnalyzer();
HiveOperation operation = SessionState.get().getHiveOperation();
JSONObject object = new JSONObject();
Object jsonInput = toJson("INPUTS", toString(analyzer.getInputs()), out, work);
if (work.isFormatted()) {
object.put("INPUTS", jsonInput);
}
Object jsonOutput = toJson("OUTPUTS", toString(analyzer.getOutputs()), out, work);
if (work.isFormatted()) {
object.put("OUTPUTS", jsonOutput);
}
String userName = SessionState.get().getAuthenticator().getUserName();
Object jsonUser = toJson("CURRENT_USER", userName, out, work);
if (work.isFormatted()) {
object.put("CURRENT_USER", jsonUser);
}
Object jsonOperation = toJson("OPERATION", operation.name(), out, work);
if (work.isFormatted()) {
object.put("OPERATION", jsonOperation);
}
if (analyzer.skipAuthorization()) {
return object;
}
final List exceptions = new ArrayList();
Object delegate = SessionState.get().getActiveAuthorizer();
if (delegate != null) {
Class itface = SessionState.get().getAuthorizerInterface();
Object authorizer = AuthorizationFactory.create(delegate, itface,
new AuthorizationFactory.AuthorizationExceptionHandler() {
public void exception(Exception exception) {
exceptions.add(exception.getMessage());
}
});
SessionState.get().setActiveAuthorizer(authorizer);
try {
Driver.doAuthorization(analyzer, "");
} finally {
SessionState.get().setActiveAuthorizer(delegate);
}
}
if (!exceptions.isEmpty()) {
Object jsonFails = toJson("AUTHORIZATION_FAILURES", exceptions, out, work);
if (work.isFormatted()) {
object.put("AUTHORIZATION_FAILURES", jsonFails);
}
}
return object;
}
private static String indentString(int indent) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < indent; ++i) {
sb.append(" ");
}
return sb.toString();
}
private JSONObject outputMap(Map mp, boolean hasHeader, PrintStream out,
boolean extended, boolean jsonOutput, int indent) throws Exception {
TreeMap tree = new TreeMap();
tree.putAll(mp);
JSONObject json = jsonOutput ? new JSONObject() : null;
if (out != null && hasHeader && !mp.isEmpty()) {
out.println();
}
for (Entry ent : tree.entrySet()) {
// Print the key
if (out != null) {
out.print(indentString(indent));
out.printf("%s ", ent.getKey().toString());
}
// Print the value
if (isPrintable(ent.getValue())) {
if (out != null) {
out.print(ent.getValue());
out.println();
}
if (jsonOutput) {
json.put(ent.getKey().toString(), ent.getValue().toString());
}
}
else if (ent.getValue() instanceof List) {
if (ent.getValue() != null && !((List)ent.getValue()).isEmpty()
&& ((List)ent.getValue()).get(0) != null &&
((List)ent.getValue()).get(0) instanceof TezWork.Dependency) {
if (out != null) {
boolean isFirst = true;
for (TezWork.Dependency dep: (List)ent.getValue()) {
if (!isFirst) {
out.print(", ");
} else {
out.print("<- ");
isFirst = false;
}
out.print(dep.getName());
out.print(" (");
out.print(dep.getType());
out.print(")");
}
out.println();
}
if (jsonOutput) {
for (TezWork.Dependency dep: (List)ent.getValue()) {
JSONObject jsonDep = new JSONObject();
jsonDep.put("parent", dep.getName());
jsonDep.put("type", dep.getType());
json.accumulate(ent.getKey().toString(), jsonDep);
}
}
} else {
if (out != null) {
out.print(ent.getValue().toString());
out.println();
}
if (jsonOutput) {
json.put(ent.getKey().toString(), ent.getValue().toString());
}
}
}
else if (ent.getValue() instanceof Map) {
if (out != null) {
out.print(ent.getValue().toString());
out.println();
}
if (jsonOutput) {
json.put(ent.getKey().toString(), ent.getValue().toString());
}
}
else if (ent.getValue() instanceof Serializable) {
if (out != null) {
out.println();
}
JSONObject jsonOut = outputPlan((Serializable) ent.getValue(), out,
extended, jsonOutput, jsonOutput ? 0 : indent + 2);
if (jsonOutput) {
json.put(ent.getKey().toString(), jsonOut);
}
}
else {
if (out != null) {
out.println();
}
}
}
return jsonOutput ? json : null;
}
private JSONArray outputList(List l, PrintStream out, boolean hasHeader,
boolean extended, boolean jsonOutput, int indent) throws Exception {
boolean first_el = true;
boolean nl = false;
JSONArray outputArray = new JSONArray();
for (Object o : l) {
if (isPrintable(o)) {
String delim = first_el ? " " : ", ";
if (out != null) {
out.print(delim);
out.print(o);
}
if (jsonOutput) {
outputArray.put(o);
}
nl = true;
}
else if (o instanceof Serializable) {
if (first_el && (out != null) && hasHeader) {
out.println();
}
JSONObject jsonOut = outputPlan((Serializable) o, out, extended,
jsonOutput, jsonOutput ? 0 : (hasHeader ? indent + 2 : indent));
if (jsonOutput) {
outputArray.put(jsonOut);
}
}
first_el = false;
}
if (nl && (out != null)) {
out.println();
}
return jsonOutput ? outputArray : null;
}
private boolean isPrintable(Object val) {
if (val instanceof Boolean || val instanceof String
|| val instanceof Integer || val instanceof Long || val instanceof Byte
|| val instanceof Float || val instanceof Double || val instanceof Path) {
return true;
}
if (val != null && val.getClass().isPrimitive()) {
return true;
}
return false;
}
private JSONObject outputPlan(Serializable work,
PrintStream out, boolean extended, boolean jsonOutput, int indent) throws Exception {
return outputPlan(work, out, extended, jsonOutput, indent, "");
}
private JSONObject outputPlan(Serializable work, PrintStream out,
boolean extended, boolean jsonOutput, int indent, String appendToHeader) throws Exception {
// Check if work has an explain annotation
Annotation note = AnnotationUtils.getAnnotation(work.getClass(), Explain.class);
String keyJSONObject = null;
if (note instanceof Explain) {
Explain xpl_note = (Explain) note;
if (extended || xpl_note.normalExplain()) {
keyJSONObject = xpl_note.displayName();
if (out != null) {
out.print(indentString(indent));
if (appendToHeader != null && !appendToHeader.isEmpty()) {
out.println(xpl_note.displayName() + appendToHeader);
} else {
out.println(xpl_note.displayName());
}
}
}
}
JSONObject json = jsonOutput ? new JSONObject() : null;
// If this is an operator then we need to call the plan generation on the
// conf and then the children
if (work instanceof Operator) {
Operator operator =
(Operator) work;
if (operator.getConf() != null) {
String appender = isLogical ? " (" + operator.getOperatorId() + ")" : "";
JSONObject jsonOut = outputPlan(operator.getConf(), out, extended,
jsonOutput, jsonOutput ? 0 : indent, appender);
if (jsonOutput) {
json = jsonOut;
}
}
if (!visitedOps.contains(operator) || !isLogical) {
visitedOps.add(operator);
if (operator.getChildOperators() != null) {
int cindent = jsonOutput ? 0 : indent + 2;
for (Operator op : operator.getChildOperators()) {
JSONObject jsonOut = outputPlan(op, out, extended, jsonOutput, cindent);
if (jsonOutput) {
((JSONObject)json.get(JSONObject.getNames(json)[0])).accumulate("children", jsonOut);
}
}
}
}
if (jsonOutput) {
return json;
}
return null;
}
// We look at all methods that generate values for explain
Method[] methods = work.getClass().getMethods();
Arrays.sort(methods, new MethodComparator());
for (Method m : methods) {
int prop_indents = jsonOutput ? 0 : indent + 2;
note = AnnotationUtils.getAnnotation(m, Explain.class);
if (note instanceof Explain) {
Explain xpl_note = (Explain) note;
if (extended || xpl_note.normalExplain()) {
Object val = null;
try {
val = m.invoke(work);
}
catch (InvocationTargetException ex) {
// Ignore the exception, this may be caused by external jars
val = null;
}
if (val == null) {
continue;
}
String header = null;
boolean skipHeader = xpl_note.skipHeader();
boolean emptyHeader = false;
if (!xpl_note.displayName().equals("")) {
header = indentString(prop_indents) + xpl_note.displayName() + ":";
}
else {
emptyHeader = true;
prop_indents = indent;
header = indentString(prop_indents);
}
// Try the output as a primitive object
if (isPrintable(val)) {
if (out != null && shouldPrint(xpl_note, val)) {
if (!skipHeader) {
out.printf("%s ", header);
}
out.println(val);
}
if (jsonOutput && shouldPrint(xpl_note, val)) {
json.put(header, val.toString());
}
continue;
}
int ind = 0;
if (!jsonOutput) {
if (!skipHeader) {
ind = prop_indents + 2;
} else {
ind = indent;
}
}
// Try this as a map
try {
// Go through the map and print out the stuff
Map mp = (Map) val;
if (out != null && !skipHeader && mp != null && !mp.isEmpty()) {
out.print(header);
}
JSONObject jsonOut = outputMap(mp, !skipHeader && !emptyHeader, out, extended, jsonOutput, ind);
if (jsonOutput && !mp.isEmpty()) {
json.put(header, jsonOut);
}
continue;
}
catch (ClassCastException ce) {
// Ignore - all this means is that this is not a map
}
// Try this as a list
try {
List l;
try {
l = (List) val;
} catch (ClassCastException e) {
Set s = (Set) val;
l = new LinkedList();
l.addAll(s);
}
if (out != null && !skipHeader && l != null && !l.isEmpty()) {
out.print(header);
}
JSONArray jsonOut = outputList(l, out, !skipHeader && !emptyHeader, extended, jsonOutput, ind);
if (jsonOutput && !l.isEmpty()) {
json.put(header, jsonOut);
}
continue;
}
catch (ClassCastException ce) {
// Ignore
}
// Finally check if it is serializable
try {
Serializable s = (Serializable) val;
if (!skipHeader && out != null) {
out.println(header);
}
JSONObject jsonOut = outputPlan(s, out, extended, jsonOutput, ind);
if (jsonOutput) {
if (!skipHeader) {
json.put(header, jsonOut);
} else {
for(String k: JSONObject.getNames(jsonOut)) {
json.put(k, jsonOut.get(k));
}
}
}
continue;
}
catch (ClassCastException ce) {
// Ignore
}
}
}
}
if (jsonOutput) {
if (keyJSONObject != null) {
JSONObject ret = new JSONObject();
ret.put(keyJSONObject, json);
return ret;
}
return json;
}
return null;
}
/**
* use case: we want to print the object in explain only if it is true
* how to do : print it unless the following 3 are all true:
* 1. displayOnlyOnTrue tag is on
* 2. object is boolean
* 3. object is false
* @param exp
* @param val
* @return
*/
private boolean shouldPrint(Explain exp, Object val) {
if (exp.displayOnlyOnTrue() && (val instanceof Boolean) & !((Boolean)val)) {
return false;
}
return true;
}
private JSONObject outputPlan(Task task,
PrintStream out, JSONObject parentJSON, boolean extended,
boolean jsonOutput, int indent) throws Exception {
if (out != null) {
out.print(indentString(indent));
out.printf("Stage: %s\n", task.getId());
}
// Start by getting the work part of the task and call the output plan for
// the work
JSONObject jsonOutputPlan = outputPlan(task.getWork(), out, extended,
jsonOutput, jsonOutput ? 0 : indent + 2);
if (out != null) {
out.println();
}
if (jsonOutput) {
parentJSON.put(task.getId(), jsonOutputPlan);
}
return null;
}
private JSONObject outputDependencies(Task task,
PrintStream out, JSONObject parentJson, boolean jsonOutput, boolean taskType, int indent)
throws Exception {
boolean first = true;
JSONObject json = jsonOutput ? new JSONObject() : null;
if (out != null) {
out.print(indentString(indent));
out.printf("%s", task.getId());
}
if ((task.getParentTasks() == null || task.getParentTasks().isEmpty())) {
if (task.isRootTask()) {
if (out != null) {
out.print(" is a root stage");
}
if (jsonOutput) {
json.put("ROOT STAGE", "TRUE");
}
}
}
else {
StringBuffer s = new StringBuffer();
first = true;
for (Task parent : task.getParentTasks()) {
if (!first) {
s.append(", ");
}
first = false;
s.append(parent.getId());
}
if (out != null) {
out.print(" depends on stages: ");
out.print(s.toString());
}
if (jsonOutput) {
json.put("DEPENDENT STAGES", s.toString());
}
}
Task currBackupTask = task.getBackupTask();
if (currBackupTask != null) {
if (out != null) {
out.print(" has a backup stage: ");
out.print(currBackupTask.getId());
}
if (jsonOutput) {
json.put("BACKUP STAGE", currBackupTask.getId());
}
}
if (task instanceof ConditionalTask
&& ((ConditionalTask) task).getListTasks() != null) {
StringBuffer s = new StringBuffer();
first = true;
for (Task con : ((ConditionalTask) task).getListTasks()) {
if (!first) {
s.append(", ");
}
first = false;
s.append(con.getId());
}
if (out != null) {
out.print(" , consists of ");
out.print(s.toString());
}
if (jsonOutput) {
json.put("CONDITIONAL CHILD TASKS", s.toString());
}
}
if (taskType) {
if (out != null) {
out.printf(" [%s]", task.getType());
}
if (jsonOutput) {
json.put("TASK TYPE", task.getType().name());
}
}
if (out != null) {
out.println();
}
return jsonOutput ? json : null;
}
public String outputAST(String treeString, PrintStream out,
boolean jsonOutput, int indent) throws JSONException {
if (out != null) {
out.print(indentString(indent));
out.println("ABSTRACT SYNTAX TREE:");
out.print(indentString(indent + 2));
out.println(treeString);
}
return jsonOutput ? treeString : null;
}
public JSONObject outputDependencies(PrintStream out, boolean jsonOutput,
boolean appendTaskType, List tasks)
throws Exception {
if (out != null) {
out.println("STAGE DEPENDENCIES:");
}
JSONObject json = jsonOutput ? new JSONObject() : null;
for (Task task : tasks) {
JSONObject jsonOut = outputDependencies(task, out, json, jsonOutput, appendTaskType, 2);
if (jsonOutput && jsonOut != null) {
json.put(task.getId(), jsonOut);
}
}
return jsonOutput ? json : null;
}
public JSONObject outputStagePlans(PrintStream out, List tasks,
boolean jsonOutput, boolean isExtended)
throws Exception {
if (out != null) {
out.println("STAGE PLANS:");
}
JSONObject json = jsonOutput ? new JSONObject() : null;
for (Task task : tasks) {
outputPlan(task, out, json, isExtended, jsonOutput, 2);
}
return jsonOutput ? json : null;
}
/**
* MethodComparator.
*
*/
public class MethodComparator implements Comparator {
@Override
public int compare(Method m1, Method m2) {
return m1.getName().compareTo(m2.getName());
}
}
@Override
public StageType getType() {
return StageType.EXPLAIN;
}
@Override
public String getName() {
return "EXPLAIN";
}
public List getResultSchema() {
FieldSchema tmpFieldSchema = new FieldSchema();
List colList = new ArrayList();
tmpFieldSchema.setName(EXPL_COLUMN_NAME);
tmpFieldSchema.setType(STRING_TYPE_NAME);
colList.add(tmpFieldSchema);
return colList;
}
}
