(TOK_QUERY 
    (TOK_FROM 
        (TOK_JOIN 
            (TOK_TABREF 
                (TOK_TABNAME kv)
             mykv)
 
            (TOK_TABREF 
                (TOK_TABNAME test)
             mytest)
 
            (== 
                (. 
                    (TOK_TABLE_OR_COL mykv)
                 key)
 
                (. 
                    (TOK_TABLE_OR_COL mytest)
                 id)
            )
        )
    )
 
    (TOK_INSERT 
        (TOK_DESTINATION 
            (TOK_DIR TOK_TMP_FILE)
        )
 
        (TOK_SELECT 
            (TOK_SELEXPR 
                (TOK_TABLE_OR_COL key)
            )
        )
    )
)

#!/usr/bin/env python
# -*- coding: utf-8 -*-
'''
Created on 2012-5-20
 
@author: fatkun
'''
import sys
 
# explain select key from kv mykv join test mytest on (mykv.key == mytest.id);
original_str = """(TOK_QUERY (TOK_FROM (TOK_JOIN (TOK_TABREF 
(TOK_TABNAME kv) mykv) (TOK_TABREF (TOK_TABNAME test) mytest) 
(== (. (TOK_TABLE_OR_COL mykv) key) (. (TOK_TABLE_OR_COL mytest) id)))) 
(TOK_INSERT (TOK_DESTINATION (TOK_DIR TOK_TMP_FILE)) (TOK_SELECT (TOK_SELEXPR (TOK_TABLE_OR_COL key)))))"""
 
tmp_str = original_str.strip().replace('\n', '')
 
def my_print(mystr):
    sys.stdout.write(mystr)
 
def print_indent(indent_level):
    for i in range(indent_level):
        my_print(' ' * 4)
 
 
indent_level = 0
for char in tmp_str:
    if char == '(':
        # 如果是左括号,先换行,然后打印缩进+(
        my_print('\n')
        print_indent(indent_level)
        my_print(char)
        indent_level += 1
    elif char == ')':
        # 如果是右括号,先打印),再换行,打印下一级别的缩进
        indent_level -= 1
        my_print(char)
        my_print('\n')
        print_indent(indent_level - 1)
    else:
        # 其他的直接打印出来
        my_print(char)

wget -c http://download.oracle.com/otn-pub/java/jdk/7/jdk-7-linux-i586.tar.gz

sudo tar zxvf ./jdk-7-linux-i586.tar.gz  -C /usr/lib/jvm  
cd /usr/lib/jvm  
sudo mv jdk1.7.0/ java-7-sun

vim ~/.bashrc

export JAVA_HOME=/usr/lib/jvm/java-7-sun  
export JRE_HOME=${JAVA_HOME}/jre  
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib  
export PATH=${JAVA_HOME}/bin:$PATH

source ~/.bashrc

sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-7-sun/bin/java 300  
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-7-sun/bin/javac 300  
sudo update-alternatives --install /usr/bin/jar jar /usr/lib/jvm/java-7-sun/bin/jar 300

sudo update-alternatives --config java

snowdream@snowdream:~$ sudo update-alternatives --config java  
有 3 个候选项可用于替换 java (提供 /usr/bin/java)。  
 
 
  选择       路径                                    优先级  状态  
------------------------------------------------------------  
* 0            /usr/lib/jvm/java-6-openjdk/jre/bin/java   1061      自动模式  
  1            /usr/lib/jvm/java-6-openjdk/jre/bin/java   1061      手动模式  
  2            /usr/lib/jvm/java-6-sun/jre/bin/java       63        手动模式  
  3            /usr/lib/jvm/java-7-sun/bin/java           300       手动模式

snowdream@snowdream:~$ java -version  
java version "1.7.0"  
Java(TM) SE Runtime Environment (build 1.7.0-b147)  
Java HotSpot(TM) Server VM (build 21.0-b17, mixed mode)

    URL hconfurl = getClassLoader().getResource("hive-default.xml");
    if (hconfurl == null) {
      l4j.debug("hive-default.xml not found.");
    } else {
      addResource(hconfurl);
    }
    URL hsiteurl = getClassLoader().getResource("hive-site.xml");
    if (hsiteurl == null) {
      l4j.debug("hive-site.xml not found.");
    } else {
      addResource(hsiteurl);
    }

<property>
 <name>datanucleus.fixedDatastore</name>
 <value>true</value>
</property>

<property>
 <name>datanucleus.autoCreateSchema</name>
 <value>false</value>
</property>

public void create_table(final Table tbl) throws AlreadyExistsException,
        MetaException, InvalidObjectException {
...
create_table_core(ms, tbl);

    private void create_table_core(final RawStore ms, final Table tbl)
        throws AlreadyExistsException, MetaException, InvalidObjectException {
//检查了一些名称，列名，分区之类的
      //...
        ms.openTransaction();
        //....
        if (!TableType.VIRTUAL_VIEW.toString().equals(tbl.getTableType())) {
          if (tbl.getSd().getLocation() == null
            || tbl.getSd().getLocation().isEmpty()) {
            tblPath = wh.getDefaultTablePath(
              tbl.getDbName(), tbl.getTableName());
          } else {
            if (!isExternal(tbl) && !MetaStoreUtils.isNonNativeTable(tbl)) {
              LOG.warn("Location: " + tbl.getSd().getLocation()
                + " specified for non-external table:" + tbl.getTableName());
            }
            // 主要就是这里啦！getDnsPath！！！帮我们把dataurl补全
            tblPath = wh.getDnsPath(new Path(tbl.getSd().getLocation()));
          }
          tbl.getSd().setLocation(tblPath.toString());
        }
 
        //...
        ms.createTable(tbl);
 
    }

  public Path getDnsPath(Path path) throws MetaException {
    FileSystem fs = getFs(path);
    return (new Path(fs.getUri().getScheme(), fs.getUri().getAuthority(), path
        .toUri().getPath()));
  }

    public void alter_table(final String dbname, final String name, final Table newTable)
        throws InvalidOperationException, MetaException {
\\...
 alterHandler.alterTable(ms, wh, dbname, name, newTable);

public void alterTable(RawStore msdb, Warehouse wh, String dbname,
      String name, Table newt) throws InvalidOperationException, MetaException {
//这里主要判断表名有没有改
//如果改了分区字段则抛错误
//如果改了表名但location没改或者为空，并且不是外部表，则把数据给移了~
 
//最后，直接的alterTable了。。？虾米，location就这样保存进去了？！
      // now finally call alter table
      msdb.alterTable(dbname, name, newt);
      // commit the changes
      success = msdb.commitTransaction();
}

if [ "$name" == "Fatkun" ]; then
    echo "Hi!Fatkun"
elif [ ... ]; then
    echo "..."
else
    echo "..."
fi

case  $變數名稱 in   <==關鍵字為 case ，還有變數前有錢字號
  "第一個變數內容")   <==每個變數內容建議用雙引號括起來，關鍵字則為小括號 )
	程式段
	;;            <==每個類別結尾使用兩個連續的分號來處理！
  "第二個變數內容")
	程式段
	;;
  *)                  <==最後一個變數內容都會用 * 來代表所有其他值
	不包含第一個變數內容與第二個變數內容的其他程式執行段
	exit 1
	;;
esac                  <==最終的 case 結尾！『反過來寫』思考一下！

while [ condition ]  <==中括號內的狀態就是判斷式
do            <==do 是迴圈的開始！
	程式段落
done          <==done 是迴圈的結束

for var in con1 con2 con3 ...
do
	程式段
done

Ext.namespace('Ext.ui.plugins');
 
 Ext.ui.plugins.ComboPageSize = function(config) {
     Ext.apply(this, config);
 };
 
 Ext.extend(Ext.ui.plugins.ComboPageSize, Ext.util.Observable, {
 
     pageSizes: [25, 50, 100, 200, 500],
     prefixText: '每页显示',
     postfixText: '条',
     addToItem: true,    //true添加到items中去，配合index；false则直接添加到最后
     index: 10,           //在items中的位置
     init: function(pagingToolbar) {
         var ps = this.pageSizes;
         var combo = new Ext.form.ComboBox({
             typeAhead: true,
             triggerAction: 'all',
             lazyRender: true,
             mode: 'local',
             width: 80,
             store: ps,
             enableKeyEvents: true,
             editable: false,
             loadPages: function() {
                 var rowIndex = 0;
                 var gp = pagingToolbar.findParentBy(
                                 function(ct, cmp) { return (ct instanceof Ext.grid.GridPanel) ? true : false; }
                               );
                 var sm = gp.getSelectionModel();
                 if (undefined != sm && sm.hasSelection()) {
                     if (sm instanceof Ext.grid.RowSelectionModel) {
                         rowIndex = gp.store.indexOf(sm.getSelected());
                     } else if (sm instanceof Ext.grid.CellSelectionModel) {
                         rowIndex = sm.getSelectedCell()[0];
                     }
                 }
                 rowIndex += pagingToolbar.cursor;
                 pagingToolbar.doLoad(Math.floor(rowIndex / pagingToolbar.pageSize) * pagingToolbar.pageSize);
             },
             listeners: {
                 select: function(c, r, i) {
                     pagingToolbar.pageSize = ps[i];
                     this.loadPages();
                 },
                 blur: function() {
                     var pagesizeTemp = Number(this.getValue());
                     if (isNaN(pagesizeTemp)) {
                         this.setValue(pagingToolbar.pageSize);
                         return;
                     }
                     pagingToolbar.pageSize = Number(this.getValue());
                     this.loadPages();
                 }
             }
         });
         if (this.addToItem) {
             var inputIndex = this.index;
             if (inputIndex > pagingToolbar.items.length) inputIndex = pagingToolbar.items.length;
             pagingToolbar.insert(++inputIndex, '-');
             pagingToolbar.insert(++inputIndex, this.prefixText);
             pagingToolbar.insert(++inputIndex, combo);
             pagingToolbar.insert(++inputIndex, this.postfixText);
         }
         else {
             pagingToolbar.add('-');
             pagingToolbar.add(this.prefixText);
             pagingToolbar.add(combo);
             pagingToolbar.add(this.postfixText);
         }
         pagingToolbar.on({
             beforedestroy: function() {
                 combo.destroy();
             },
             change: function() {
                 combo.setValue(pagingToolbar.pageSize);
 
             }
         });
 
     }
 })

                bbar: new Ext.PagingToolbar({
                    plugins: new Ext.ui.plugins.ComboPageSize(),
                    pageSize: myPageSize,
                    displayInfo : true,
                    displayMsg : '当前记录数: {0} - {1} 总记录数: {2}',   
                    emptyMsg : '没有符合条件的记录',   
                    store : config.store
                })