2007
08.31
Don’t ask why I come up with this post 
Let’s just say it has something to do with Regular Expression.
The first method that immediately come up to mind (and usually the worst ) is as follows:
struct Res
{
//To Record the Result
public String words;
public int wordcount;
}
public static Res WorstWordByLengthSort(string raw)
{
Res myresult = new Res();
myresult.wordcount = 0;
string[] words = raw.Split("n".ToCharArray());
raw = "";
foreach (string word in words)
raw += word + " ";
words = raw.Split(" ".ToCharArray());
ArrayList ar = new ArrayList();
foreach (string word in words)
{
string tstr = word.Trim();
if (tstr == "")
continue;
myresult.wordcount++;
if (ar.Count == 0)
{
ar.Add(tstr);
}
else
{
int count = ar.Count;
bool inserted = false;
for (int i = 0; i < count; i++)
{
if (ar[i].ToString().Length <= tstr.Length)
{
if (!ar.Contains(tstr))
{
ar.Insert(i, tstr);
inserted = true;
}
}
}
if (!inserted && !ar.Contains(tstr))
ar.Add(tstr);
}
}
StringBuilder sb = new StringBuilder();
foreach (object o in ar)
sb.AppendLine(o.ToString());
myresult.words= sb.ToString();
return myresult;
}
It will work flawlessly (sort of .. ), but it will not allow duplication of word. After tinkering for a while, I came up with an idea to improve its performance. A better solution would be to use a dictionary where the length of the word becomes the key. If a key is already exist in the dictionary, we just simply append the word into the value of that particular key. The idea is implemented as follows:
struct Res
{
//To Record the Result
public String words;
public int wordcount;
}
public static Res BetterWordByLengthSort(string raw)
{
Res myresult = new Res();
myresult.wordcount = 0;
myresult.words = "";
StringBuilder result = new StringBuilder();
Dictionary myDict = new Dictionary();
ArrayList keys = new ArrayList();
string[] words = raw.Split("n".ToCharArray());
raw = "";
foreach (string word in words)
{
string tword = word.Trim();
raw += tword + " ";
}
words = null;
words = raw.Split(" ".ToCharArray());
foreach (string word in words)
{
string tempWord = word.Trim();
if (tempWord == "")
continue;
int tlength = tempWord.Length;
if (myDict.ContainsKey(tlength))
{
myDict[tlength] = myDict[tlength] + "n" + tempWord;
}
else
{
keys.Add(tlength);
myDict.Add(tlength, tempWord);
}
myresult.wordcount++;
}
//Sort the keys ASC
keys.Sort();
for (int i=keys.Count-1; i>=0; i--)
{
result.AppendLine(myDict[(int)keys[i]]);
}
myresult.words = result.ToString();
return myresult;
}
I created a GUI project to compare their performance. With same input of 1443 words, the Worst method took 734 ms, while the Better method took only 15 ms. And yes, if you remember your Big O complexity, the Better method is definitely much more efficient compared to the Worst method
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2007
08.30
As I promised before, I will put the output of the programs that I mention in the previous post.
As input I will use the following SQL string (which I have verified that it is a valid SQL statement).
ALTER PROCEDURE [dbo].[aspnet_Setup_RemoveAllRoleMembers] @name sysname AS BEGIN CREATE TABLE #aspnet_RoleMembers ( Group_name sysname, Group_id smallint, Users_in_group sysname, User_id smallint ); INSERT INTO #aspnet_RoleMembers EXEC sp_helpuser @name; DECLARE @user_id smallint; DECLARE @cmd nvarchar(500); DECLARE c1 cursor FORWARD_ONLY FOR SELECT User_id FROM #aspnet_RoleMembers; OPEN c1; FETCH c1 INTO @user_id; WHILE (@@fetch_status = 0) BEGIN SET @cmd = 'EXEC sp_droprolemember ' + '''' + @name + ''', ''' + USER_NAME(@user_id) + ''''; EXEC (@cmd); FETCH c1 INTO @user_id END; CLOSE c1; DEALLOCATE c1 END
The output of the program are as follows:
- SQLinForm
ALTER
PROCEDURE [dbo].[aspnet_Setup_RemoveAllRoleMembers] @name sysname
AS
BEGIN
CREATE TABLE #aspnet_RoleMembers
(
Group_name sysname ,
Group_id smallint ,
Users_in_group sysname,
User_id smallint
);
INSERT INTO #aspnet_RoleMembers EXEC sp_helpuser @name;
DECLARE @user_id smallint;
DECLARE @cmd nvarchar(500);
DECLARE c1
cursor FORWARD_ONLY FOR
SELECT User_id FROM #aspnet_RoleMembers;
OPEN c1;
FETCH c1 INTO @user_id;
WHILE (@@fetch_status = 0)
BEGIN
SET @cmd = 'EXEC sp_droprolemember ' + '''' + @name + ''', ''' + USER_NAME(@user_id) + '''';
EXEC (@cmd);
FETCH c1 INTO @user_id
END;
CLOSE c1;
DEALLOCATE c1
END
Initially I thought there was missing ‘END’, but I found out that because I choose ‘Any SQL’ instead of ‘SQL Server’. Very impressive!!!
- SQL Online Formatter
ALTER PROCEDURE [DBO].[ASPNET_SETUP_REMOVEALLROLEMEMBERS]
@name SYSNAME
AS
BEGIN
CREATE TABLE #ASPNET_ROLEMEMBERS (
GROUP_NAME SYSNAME,
GROUP_ID SMALLINT,
USERS_IN_GROUP SYSNAME,
USER_ID SMALLINT);
INSERT INTO #ASPNET_ROLEMEMBERS
EXEC SP_HELPUSER
@name;
DECLARE @user_id SMALLINT;
DECLARE @cmd NVARCHAR(500);
DECLARE C1 CURSOR FORWARD_ONLY FOR
SELECT USER_ID
FROM #ASPNET_ROLEMEMBERS;
OPEN C1;
FETCH C1
INTO @user_id;
WHILE (@@FETCH_STATUS = 0)
BEGIN
SET @cmd = 'EXEC sp_droprolemember ' + '''' + @name + ''', ''' + USER_NAME(@user_id) + '''';
EXEC( @cmd);
FETCH C1
INTO @user_id
END;
CLOSE C1;
DEALLOCATE C1
END
As you see, it also performs as good as SQLinForm
- SQL Review
ALTER PROCEDURE [dbo].[aspnet_Setup_RemoveAllRoleMembers] @name sysname AS
BEGIN
CREATE TABLE #aspnet_RoleMembers (
Group_name sysname,
Group_id smallint,
Users_in_group sysname,
User_id smallint
);
INSERT INTO #aspnet_RoleMembers
EXEC sp_helpuser @name;
DECLARE
@user_id smallint;
DECLARE
@cmd nvarchar(500);
DECLARE
c1
CURSOR FORWARD_ONLY
FOR
SELECT
User_id
FROM
#aspnet_RoleMembers;
OPEN c1;
FETCH c1 INTO @user_id;
WHILE (@@fetch_status = 0)
BEGIN
SET @cmd = 'EXEC sp_droprolemember ' + '''' + @name + ''', ''' + USER_NAME(@user_id) + '''';
EXEC (@cmd);
FETCH c1 INTO @user_id
END;
CLOSE c1;
DEALLOCATE c1
END
Unfortunately there is no option to indent text between BEGIN and END. But the plus point is you can run it
- Pl/sql tidy
Hmm.. doesn’t seem to work. Is it because it only parse PL/SQL? (I will investigate further when I really have nothing to do 
)
As for the LEX script, I’m still trying to get it work on C# using CsLEX, so it would take sometime before I post the result here.
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2007
08.29
Once in a while, I log in to MyBlogLog (It’s the social network site for bloggers). In my profile, I put “Sticks and stones love, I saved your life and you saved mine, we’re square” … oops .. … I mean “If you add me, I will add you”, or something like that …
After quite sometime my list of contacts grows until 299. I have around 5 people that have added me to their contact, but MyBlogLog didn’t allow me to return the favour by adding them into my contact. I forgot when exactly this thing happened, maybe roughly 2-3 months ago? After trying for 1 or two days, I stopped trying.
So today I login again to MyBlogLog and found there are 35 people who have added me. Without any intention or expectation, I clicked the add to contact button.. Whoa.. I can now add more people into my contact list. Since when did this happen?
To all MyBlogLog-gers, I offer you my humble apology for not keeping my word of adding you into my contact list. I will definitely return the favour.
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