python dataframe是否像oracle connect_by一样?

时间:2017-11-03 23:02:17

标签: python oracle pandas dataframe

在oracle中,我可以为父子层次结构做这样的事情。这非常方便。现在我在pandas dataframe

中做相同的操作
with tab1zx as (
select 1 as id, null as parent_id from dual union
select 2 as id, 1 as parent_id from dual union
select 3 as id, 2 as parent_id from dual union
select 4 as id, 2 as parent_id from dual union
select 5 as id, 4 as parent_id from dual union
select 6 as id, 4 as parent_id from dual union
select 7 as id, 1 as parent_id from dual union
select 8 as id, 7 as parent_id from dual union
select 9 as id, 1 as parent_id from dual union
select 10 as id, 9 as parent_id from dual union
select 11 as id, 10 as parent_id from dual union
select 12 as id, 9 as parent_id from dual

)
--select * from tab1zx
SELECT id,
       parent_id,
       RPAD('.', (level-1)*2, '.') || id AS tree,
       level,
       CONNECT_BY_ROOT id AS root_id,
       LTRIM(SYS_CONNECT_BY_PATH(id, '-'), '-') AS path,
       CONNECT_BY_ISLEAF AS leaf
FROM   tab1zx
START WITH parent_id IS NULL
CONNECT BY parent_id = PRIOR id
ORDER SIBLINGS BY id;

现在,如果我有一个python数据帧,我该怎么做

aa={
    'id':["1","2","3","4","5","6","7","8","9","10","11","12"]
    ,'parent_id':["","1","2","2","4","4","1","7","1","9","10","9"]
}

import pandas as pd
df=pd.DataFrame.from_dict(aa)

1 个答案:

答案 0 :(得分:2)

您可以尝试制作笛卡尔积并过滤它:

Me.subRegisterModuleForToString

PS AFAIK对于Pandas中的Oracle %REM Class DebuggingScriptsObjectBASE <!-- Created Jun 9, 2017 by JSmart523 --> <!-- If you're reading this, hover your mouse pointer over "DebuggingScriptsObjectBASE" in the Class statement after this comment. --> This is intended to be the common ancestor object for all custom objects you write. The benefit is fsToString() and ToString() methods. Other classes and procedures of this script library do not require that your objects inherit from this one. <br> The best way to use it is,<ol> <li>Have all of your custom classes inherit (directly or indirectly) from this class. <li>Follow the best practice of only having one class per script library, or at least create your script libraries so no classes descend from any classes within the same script library. <li>In the constructor sub (New) of each class, call Me.subRegisterModuleForToString(CLASSNAME) where CLASSNAME is the name of the class. (Yes, unfortunately you have to hardcode this. No better way was found, LotusScript is not a completely reflective language and TypeName() doesn't work for parent-classes.) <li>When logging errors or other debugging messages and wanting to mention the current object in your message, use Me.fsToString() to generate the name of your object. <li>If <code>TypeName(Me)</code> is insufficient for the name of your object, override Me.ToString() (not Me.<em>fs</em>ToString()) to return whatever makes sense. </ol> If you do this then, any time your code logs something and wants to generate a string representing your object,<ul> <li>if the code doing so is defined in the actual class of the object, it will still return Me.ToString(), however, <li>if the code doing so is NOT defined in the actual class but in an ancestor class then, Me.fsToString() will return <span style="font-family: monospace; color: black;">sCodeClass <font style="color: blue;">+</font> "(" <font style="color: blue;">+ Me.</font>ToString<font style="color: blue;">()+</font> ")"</span>, for example "ParentClass(ChildClass)" which is much better at describing where the code in question is.</ul> <br> If you don't follow the best practice of only havng one class per script library and instead define classes that inherit other classes within the same script lilbrary (e.g. this script library combines almost all it needs into a single script library so it is more easily packaged), but still want to inherit from this object then do not call Me.subRegisterModuleForToString nor Me.fsToString from within your class, use Me.fsToString_FromCodeClass instead and pass the name of your class as the method's argument. <br> Also included in this class is a LogLevel integer property. You can use this in your coding to determine how verbose your logging should be, with 0 as normal. For example, if your class has a DoTheThing method you might want that method's code to be: <blockquote> <pre><div style="font-family: monospace; font-size: 9pt; color: black;"><font style="color: blue;">Class</font> YourClass <font style="color: blue;">As</font> DebuggingScriptsObjectBASE &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">Sub New()</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">If Not</font> libbDebugMode <font style="color: blue;">Then On Error GoTo</font> LogAndThrowError &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">Me.</font>subRegisterModuleForToString<font style="color: blue;">(</font><font style="color: black;">"YourClass"</font><font style="color: blue;">)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">Exit Sub</font> LogAndThrowError<font style="color: blue;">:</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;LogErrorForObject <font style="color: blue;">Err, Erl, Error$, Me.</font>fsToString<font style="color: blue;">(),</font> <font style="color: black;">""</font><font style="color: blue;">,</font> <font style="color: black;">""</font><font style="color: blue;">,</font> <font style="color: black;">""</font><font style="color: blue;">,</font> <font style="color: purple;">True</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">End Sub</font> <br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">Sub</font> DoTheThing<font style="color: blue;">(</font>db <font style="color: blue;">As</font> <font style="color: black;">NotesDatabase</font><font style="color: blue;">,</font> doc <font style="color: blue;">As</font> <font style="color: black;">NotesDocument</font><font style="color: blue;">,</font> vArg3 <font style="color: blue;">As Variant)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">If Not</font> libbDebugMode <font style="color: blue;">Then On Error GoTo</font> LogAndThrowError &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">If Me.</font>LogLevel <font style="color: blue;">&#62;</font> 0 <font style="color: blue;">Then</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">Dim</font> oIndent <font style="color: blue;">As New</font> MortalIndent<font style="color: blue;">(</font><font style="color: black;">""</font><font style="color: blue;">,</font> <font style="color: black;">"Starting "</font> <font style="color: blue;">+ Me.</font>fsToString<font style="color: blue;">() +</font> <font style="color: black;">".DoTheThing"</font><font style="color: blue;">,</font> <font style="color: black;">"Exiting "</font> <font style="color: blue;">+ Me.</font>fsToString<font style="color: blue;">() +</font> <font style="color: black;">".DoTheThing"</font><font style="color: blue;">)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">If Me.</font>LogLevel <font style="color: blue;">&#62;</font> 1 <font style="color: blue;">Then</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;LogAction <font style="color: black;">"db = "</font> <font style="color: blue;">+</font> fsStringifyForDebugging<font style="color: blue;">(</font>db<font style="color: blue;">,</font> <font style="color: purple;">True</font><font style="color: blue;">)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;LogAction <font style="color: black;">"doc = "</font> <font style="color: blue;">+</font> fsStringifyForDebugging<font style="color: blue;">(</font>doc<font style="color: blue;">,</font> <font style="color: purple;">True</font><font style="color: blue;">)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;LogAction <font style="color: black;">"vArg3 = "</font> <font style="color: blue;">+</font> fsStringifyForDebugging<font style="color: blue;">(</font>vArg3<font style="color: blue;">,</font> <font style="color: purple;">True</font><font style="color: blue;">)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">End If</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">End If</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: green;">'MAIN CODE WOULD GO HERE</font> <br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">Exit Sub</font> LogAndThrowError<font style="color: blue;">:</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;LogErrorForObject <font style="color: blue;">Err, Erl, Error$, Me.</font>fsToString<font style="color: blue;">(),</font> <font style="color: black;">""</font><font style="color: blue;">,</font> ToArray3<font style="color: blue;">(</font>db<font style="color: blue;">,</font> doc<font style="color: blue;">,</font> vArg3<font style="color: blue;">),</font> <font style="color: black;">""</font><font style="color: blue;">,</font> <font style="color: purple;">True</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">End Sub</font> <font style="color: blue;">End Class</font></div></pre> <!-- Huge thanks to Julian Robichaux's LS2HTML script at http://www.nsftools.com/tips/ls2html.lss --> </blockquote> so that, if an object of that class has a LogLevel property value greater than zero then this script library will log when the method starts, and stops, and indent all of the log entries in the middle, and if the LogLevel value is greater than 1 then it also logs the arguments. Also, if another class extends YourClass then the log messages will explain that the code is contained within YourClass, not the descendant class. %END REM Public Class DebuggingScriptsObjectBASE 'Private list of classes, indexed by the module (i.e. script library) they are contained in Private plstsClassByModule List As String %REM Private Sub subRegisterModuleForToString(sClassName As String) If you call <code>Me.subRegisterModuleForToString("MyClassName")</code> from your class's New sub, when this specific class calls Me.fsToString() the returned string will indicate that it was called by this specific class. This greatly helps avoid confusion when trying to figure out which class contains the code that logged the error. Stores <code>sClassName</code> into a list of class names, indexed by the module (aka script library) that defines them. <br> Unfortunately there's no way for a method to be able to tell which ancestor class or descendant class (if any) called it, but we CAN tell which <em>design element</em> contains the code that called the method. By calling this in each class's constructor sub, your objects build a "Design Element to CodeClass" map for themselves. Then, if Me.fsToString is called, while there isn't any native LotusScript to determine which class defines the code that called it, it can derrive the ClassCode via <code>Me.plstsClassByModule(GetThreadInfo(LSI_THREAD_CALLMODULE))</code> <br> <b>Arguments</b> <blockquote><dl><dt>sClassName As String</dt><dd>Name of the class that is calling this method.</dd></dl></blockquote> %END REM Private Sub subRegisterModuleForToString(sClassName As String) If Not libbDebugMode Then On Error GoTo LogAndThrowError Dim sCallModule As String sCallModule = GetThreadInfo(LSI_THREAD_CALLMODULE) If Len(sClassName) = 0 Then Error 13, Me.ToString() + ".subRegisterModuleForToString's argument cannot be blank." ElseIf Not IsElement(Me.plstsClassByModule(sCallModule)) Then 'remember that script library sCallModule defines sClassName Me.plstsClassByModule(sCallModule) = sClassName ' Me.subAddToClassNames sClassName ElseIf Me.plstsClassByModule(sCallModule) <> sClassName Then Error DebuggingScripts_ERROR_CodeClassConflict, {If both "} + sClassName + {" and "} + Me.plstsClassByModule(sCallModule) + {" are defined within module "} + sCallModule + {", neither should call subRegisterModuleForToString. Please either move one of the classes to its own script libraray or change that class so that all calls to Me.fsToString() instead call Me.fsToString_FromCodeClass("YourClassName")} 'Else 'We don't need to do anything. Me.plstsClassByModule(sCallModule) is already sClassName! End If Exit Sub LogAndThrowError: 'Replace error handling with whatever you use LogErrorForObject Err, Erl, Error$, "DebuggingScriptsObjectBASE", "", sClassName, sCallModule, True End Sub %REM Public Function ToString As String Unless you override this function, returns <code>TypeName(Me)</code> You can override this for a class that inherits from this one. For example, if class Foo extends this one, and a Foo object was always in the "foo" property of it's parent object, you might want Foo.ToString() to override this function with the following code: <pre><div style="font-family: monospace; font-size: 9pt; color: black;"><font style="color: blue;">Public</font> <font style="color: blue;">Function</font> ToString <font style="color: blue;">As</font> <font style="color: blue;">String</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">On</font> <font style="color: blue;">Error</font> <font style="color: blue;">Resume</font> <font style="color: blue;">Next</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ToString <font style="color: blue;">=</font> DebuggingScriptsObjectBASE<font style="color: blue;">.</font><font style="color: blue;">.</font>ToString<font style="color: blue;">(</font><font style="color: blue;">)</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">If</font> <font style="color: blue;">Not</font> <font style="color: blue;">Me</font><font style="color: blue;">.</font>Parent <font style="color: blue;">Is</font> <font style="color: purple;">Nothing</font> <font style="color: blue;">Then</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">If</font> <font style="color: blue;">Me</font><font style="color: blue;">.</font>Parent<font style="color: blue;">.</font>foo <font style="color: blue;">Is</font> <font style="color: blue;">Me</font> <font style="color: blue;">Then</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ToString <font style="color: blue;">=</font> Parent<font style="color: blue;">.</font>ToString<font style="color: blue;">(</font><font style="color: blue;">)</font> <font style="color: blue;">+</font> <font style="color: black;">".foo"</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">End</font> <font style="color: blue;">If</font> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font style="color: blue;">End</font> <font style="color: blue;">If</font> <font style="color: blue;">End</font> <font style="color: blue;">Function</font></div></pre> <!-- Huge thanks to Julian Robichaux's LS2HTML script at http://www.nsftools.com/tips/ls2html.lss --> If you override, <strong>be <i>sure</i> that your ToString code will not cause an infinite loop.</strong> Within your ToString code this probably means: - Do not call Me.ToString() - Do not call Me.fsToString() - Do not send Me as an argument to fsStringifyForDebugging because it will try the ToString method. - Do not send Me as an argument to any logging functions in this script library because they use fsStringifyForDebugging - Do not call procedures where, if there's an error, any of the above might happen. %END REM Public Function ToString As String On Error GoTo ErrorSub ToString = TypeName(Me) ExitSub: Exit Function ErrorSub: ToString = "¿¿TypeName(Me) failed??" Resume ExitSub End Function %REM Private Function fsToString As String <!-- Created Jun 9, 2017 by JSmart523 --> Returns <code>fsToString_FromCodeClass(Me.plstsClassByModule(GetThreadInfo(LSI_THREAD_CALLMODULE)))</code> <br> If the calling module isn't an index value in the list Me.plstsClassByModule (populated via Me.subRegisterModuleForToString), or the class is the last descendant class for Me, returns <code>Me.ToString()</code> Otherwise returns a string like "CodeClass(ObjectToString)" where<ul><li>"CodeClass" is <code>Me.plstsClassByModule(GetThreadInfo(LSI_THREAD_CALLMODULE))</code>, and<li>"ObjectToString" is <code>Me.ToString()</code> (which is usually <code>TypeName(Me)</code>).</ul> This function requires the following assumptions: - Your class would have called Me.subRegisterModuleForToString("YourClassName") if you wanted to use this enhanced functionality. - The design element that contains your class does not also contain any classes that extend or are an ancestor of this class. Calls Me.fsToString_FromCodeClass, Me.ToString %END REM Private Function fsToString As String Dim sModule As String If Not libbDebugMode Then On Error GoTo TypeNameError fsToString = TypeName(Me) If Not libbDebugMode Then On Error GoTo LogAndExit sModule = GetThreadInfo(LSI_THREAD_CALLMODULE) If IsElement(Me.plstsClassByModule(sModule)) Then fsToString = fsToString_FromCodeClass(Me.plstsClassByModule(sModule)) Else fsToString = Me.ToString() End If ExitSub: Exit Function TypeNameError: fsToString = "{??Unknown object because fsToStringFailed??}" LogErrorForObject Err, Erl, "Error attempting TypeName(Me): " + Error$, "DebuggingScriptsObjectBASE", "", "", "", False Resume ExitSub LogAndExit: fsToString = "{??Unknown object because fsToStringFailed??}" LogErrorForObject Err, Erl, Error$, Me, "", "", "", False Resume ExitSub End Function %REM Private Function fsToString_FromCodeClass(sCodeClass As String) As String Compares sCodeClass to TypeName(Me) and &nbsp;&nbsp;- if the same, returns Me.ToString &nbsp;&nbsp;- if different, returns <code>sCodeClass + "(" + Me.ToString + ")"</code> <br> <b>Arguments</b> <blockquote><dl><dt>sCodeClass As String</dt><dd>Name of the class containing the code in question (as opposed to TypeName(Me) which is just the end class even if the code in question is defined within a class that TypeName(Me) descends from.</dd></dl></blockquote> Called by Me.fsToString(), and any objects that want to use this standard of logging the code-defining class <em>and</em> <code>TypeName(Me)</code> in a common format but (due to having ancestor objects in the same script library) Me.fsToString() is not suitable. (For example, for portability, several classes are defined withn this "DebuggingScripts" script library, and all of them inherit from DebuggingScriptsObjectBASE.) %END REM Private Function fsToString_FromCodeClass(sCodeClass As String) As String On Error Resume Next fsToString_FromCodeClass = TypeName(Me) 'in case the next line fails fsToString_FromCodeClass = Me.ToString() If UCase(sCodeClass) <> TypeName(Me) And Len(sCodeClass) <> 0 Then fsToString_FromCodeClass = sCodeClass + "(" + fsToString_FromCodeClass + ")" End If End Function End Class 没有高效的模拟