Get all Unique charactres from a column in table - SQL
i have a reqiurement to find out all unique characters avialable in a given column from table
following is the content in a coulmn
SNO NOTE_TEXT (column Name)
------------------------
1 Recovery for 1125.00 voided due to incorrect re-insurance allocation.
Now booked to 2 FR3270.
2 salvage cheque awaited
3 you. cdm_char_13 cdm_char_10 cdm_char_13 cdm_char_10 It is at:
cdm_char_13cdm_char_10 Walmgate Road Police Car Pound cdm_char_13 cdm_char_10
Walmgate Road cdm_char_13 cdm_char_10 Perivale cdm_char_13 cdm_char_10 London
cdm_char_13 cdm_char_10 UB6 7LR
Requirement:-
Need to identify all unique characte开发者_如何学JAVArs avilable in NOTE_TEXT column output shoud look like
A
B
C
.
.
Z
a
.
.
z
0
1
2
.
9
~
!
@
#
$
.
.
.
.
like this all avilabe unique characters from the table column
Try this code -
CREATE TABLE [dbo].[table1](
[column1] [varchar](50) NULL
)
GO
INSERT INTO [dbo].[table1] VALUES ('abc')
INSERT INTO [dbo].[table1] VALUES ('acbd')
INSERT INTO [dbo].[table1] VALUES ('cbde')
GO
DECLARE @column1 varchar(50);
DECLARE @text varchar(max);
DECLARE @i int;
DECLARE cur CURSOR FOR SELECT column1 FROM dbo.table1;
SET @text = '';
OPEN cur;
FETCH NEXT FROM cur INTO @column1;
WHILE @@FETCH_STATUS = 0 BEGIN
SET @i = 1;
WHILE @i <= LEN(@column1) BEGIN
IF CHARINDEX(SUBSTRING(@column1, @i, 1), @text) = 0
SET @text = @text + SUBSTRING(@column1, @i, 1);
SET @i = @i + 1;
END;
FETCH NEXT FROM cur INTO @column1;
END;
CLOSE cur;
DEALLOCATE cur;
SELECT @text;
GO
------------------------------------------------------
abcde
(1 row(s) affected)
General approach: create a table of characters, 'CROSS JOINto your
Notestable, replace the character from the characters table with the empty string and use the respective lengths to calculate the number of occurrences for that row, then
SUM...GROUP BY` each character.
I don't know Sybase DB so here's some Standard SQL (well, except for the REPLACE()
function, which most SQLs have an equivalent of):
WITH Notes (SNO, NOTE_TEXT)
AS
(
SELECT SNO, CAST(NOTE_TEXT AS VARCHAR(200))
FROM (
VALUES (1, 'Recovery for 1125.00 voided due to incorrect re-insurance allocation. Now booked to 2 FR3270.'),
(2, 'salvage cheque awaited'),
(3, 'you. cdm_char_13 cdm_char_10 cdm_char_13 cdm_char_10 It is at: cdm_char_13 cdm_char_10 Walmgate Road Police Car Pound cdm_char_13 cdm_char_10 Walmgate Road cdm_char_13 cdm_char_10 Perivale cdm_char_13 cdm_char_10 London cdm_char_13 cdm_char_10 UB6 7LR')
) AS Notes (SNO, NOTE_TEXT)
),
Characters (chars)
AS
(
SELECT CAST(chars AS CHAR(1))
FROM (
VALUES ('A'),
('B'),
-- ...
('Q'),
-- ...
('Y'),
('Z')
) AS Characters (chars)
),
CharacterNoteTallies (SNO, NOTE_TEXT, chars, chars_tally)
AS
(
SELECT N1.SNO, N1.NOTE_TEXT, C1.chars,
DATALENGTH(N1.NOTE_TEXT)
- DATALENGTH(REPLACE(N1.NOTE_TEXT, C1.chars, ''))
AS chars_tally
FROM Notes AS N1
CROSS JOIN Characters AS C1
)
SELECT T1.chars, SUM(T1.chars_tally) AS chars_tally
FROM CharacterNoteTallies AS T1
GROUP
BY T1.chars;
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