How can I "dynamically" split a varchar column by specific characters? - sql

I have a column that stores 2 values. Example below:
| Column 1 |
|some title1 =ExtractThis ; Source Title12 = ExtractThis2|
I want to remove 'ExtractThis' into one column and 'ExtractThis2' into another column. I've tried using a substring but it doesn't work as the data in column 1 is variable and therefore it doesn't always carve out my intended values. SQL below:
SELECT substring(d.Column1,13,24) FROM dbo.Table d
This returns 'Extract This' but for other columns it either takes too much or too little. Is there a function or combination of functions that will allow me to split consistently on the character? This is consistent in my column unlike my length count.


select substring(col1,CHARINDEX('=',col1)+1,CHARINDEX (';',col1)-CHARINDEX ('=',col1)-1) Val1,
substring(col1,CHARINDEX('=',col1,CHARINDEX (';',col1))+1,LEN(col1)) Val2
from #data
there is duplicate calculation that can be reduced from 5 to 3 to each line.
but I want to believe this simple optimization done by SQL SERVER.

Related

Aggregating / Concatenation of very long Varchar2 strings and find key words in the text || Oracle

I have been given a task to develop a script/ function/ query to aggregate groups of rows in a table and then search for specific keywords in it. The column to be aggregated is a varchar2 column with size 3200 and some of the aggregated rows have lengths way beyond 5000.
(I understand that the size of varchar2 is 4000)
When I try to aggregate the data into a single column, it gives a "result of string concatenation is too long" error (ORA-01489)
I have tried inbuilt aggregators like LISTAGG, XMLAGG, and also some custom functions but I have been asked to prefer a SQL query over a function or procedure.
Once I can get the data to be aggregated, I have to then search through the rows for matching keywords.
(can't just search the rows without aggregating as some of the words are split across the rows, eg row1 ends with "KEYW" and row2 starts with "ORD" if I need to look for "KEYWORD" in the table
my table kind of looks like this (can't post the real table data, sorry),
id_1 | id_2 | name | row_num | description
1 5 A 0 this has so
1 5 A 1 me keyword
1 5 B 0 this is
1 3 E 0 new some
2 12 A 0 diff str
here the unique rows are identified using the first 3 columns and the 4th column lists the order in which these "description" strings need to be concatenated.
I would like to get the output as:
id_1 | id_2 | name | description (concated)
1 5 A this is **some** keyword
1 3 E new **some**
when looking for the keyword "some"
Please help as I am fairly new to DBs and any help will be highly appreciated.
Thanks & Regards
Kunal

SQL add column value based on another column ACCESS

What I'm trying to do is add another column to an existing table whose value will depend on an already existing column in the table. For example say I have this table:
Table1
|Letter|
A
C
R
A
I want to create another column (for example, numbers) that is chosen based on the letters. So let's say A corresponds with 10, C with 3 and R with 32 (this was chosen at random). My resulting table should be like this:
|Letter| Number |
A | 10
C | 3
R | 32
A | 10
Can anyone help me write a query that does this..I have over 20 different cases, so the simpler it looks the better.
Thanks in advance!

Options:
Build a table that associates [Letter] with the numeric value. Include this table in query by joining on the common [Letter] fields.
A very long Switch() expression. However, query design grid cell has a limit of 1024 characters.
Better to provide example with your real data and criteria.

Splitting Data in a Column

I get some data that comes in to the table.
This table is currently only displaying after I merged all the tables. So you currently see:
Table 1
union
Table 2
union
Table 3
The issue I have is now i have one column in there where it contains data like this:
AA2B133
I want to split this column, so in the current column it tries to keep the first 3 charachters and the other 4 charachters it goes into another column.
What is the best way or simplest way of doing this.
Thank you

You can use the RIGHT() and LEFT() functions to split the data into multiple columns.
For example:
SELECT LEFT(data,3), RIGHT(data,4)
FROM (SELECT 'AA2B133' AS data) A
Will return two columns with the breakout you requested.

You can use Java to get the 3 first caracters using this
String substring (String s, int start, int len)
so if you want to get the three first charachters for example you can do like this
String substring ("AA2B133",0,2)

Explode range of integers out for joining in SQL

I have one table that stores a range of integers in a field, sort of like a print range, (e.g. "1-2,4-7,9-11"). This field could also contain a single number.
My goal is to join this table to a second one that has discrete values instead of ranges.
So if table one contains
1-2,5
9-15
7
And table two contains
1
2
3
4
5
6
7
8
9
10
The result of the join would be
1-2,5 1
1-2,5 2
1-2,5 5
7 7
9-15 9
9-15 10
Working in SQL Server 2008 R2.

Use a string split function of your choice to split on comma. Figure out the min/max values and join using between.
SQL Fiddle
MS SQL Server 2012 Schema Setup:
create table T1(Col1 varchar(10))
create table T2(Col2 int)
insert into T1 values
('1-2,5'),
('9-15'),
('7')
insert into T2 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10)
Query 1:
select T1.Col1,
T2.Col2
from T2
inner join (
select T1.Col1,
cast(left(S.Item, charindex('-', S.Item+'-')-1) as int) MinValue,
cast(stuff(S.Item, 1, charindex('-', S.Item), '') as int) MaxValue
from T1
cross apply dbo.Split(T1.Col1, ',') as S
) as T1
on T2.Col2 between T1.MinValue and T1.MaxValue
Results:
| COL1 | COL2 |
----------------
| 1-2,5 | 1 |
| 1-2,5 | 2 |
| 1-2,5 | 5 |
| 9-15 | 9 |
| 9-15 | 10 |
| 7 | 7 |

Like everybody has said, this is a pain to do natively in SQL Server. If you must then I think this is the proper approach.
First determine your rules for parsing the string, then break down the process into well-defined and understood problems.
Based on your example, I think this is the process:
Separate comma separated values in the string into rows
If the data does not contain a dash, then it's finished (it's a standalone value)
If it does contain a dash, parse the left and right sides of the dash
Given the left and right sides (the range) determine all the values between them into rows
I would create a temp table to populate the parsing results into which needs two columns:
SourceRowID INT, ContainedValue INT
and another to use for intermediate processing:
SourceRowID INT, ContainedValues VARCHAR
Parse your comma-separated values into their own rows using a CTE like this Step 1 is now a well-defined and understood problem to solve:
Turning a Comma Separated string into individual rows
So your result from the source
'1-2,5'
will be:
'1-2'
'5'
From there, SELECT from that processing table where the field does not contain a dash. Step 2 is now a well-defined and understood problem to solve These are standalone numbers and can go straight into the results temp table. The results table should also get the ID reference to the original row.
Next would be to parse the values to the left and right of the dash using CHARINDEX to locate it, then the appropriate LEFT and RIGHT functions as needed. This will give you the starting and ending value.
Here is a relevant question for accomplishing this step 3 is now a well-defined and understood problem to solve:
T-SQL substring - separating first and last name
Now you have separated the starting and ending values. Use another function which can explode this range. Step 4 is now a well-defined and understood problem to solve:
SQL: create sequential list of numbers from various starting points
SELECT all N between #min and #max
What is the best way to create and populate a numbers table?
and, also, insert it into the temp table.
Now what you should have is a temp table with every value in the exploded range.
Simply JOIN that to the other table on the values now, then to your source table on the ID reference and you're there.

My suggestion is to add one more field and many more records to your ranges table. Specifically, the primary key would be the integer and the other field would be the range. Records would look like this:
number range
1 1-2,5
2 1-2,5
3 na
4 na
5 1-2,5
etc
Having said that, this is still rather limiting because a number can only have one range. If you want to be thorough, set up a many to many relationship between numbers and ranges.

As far as I can tell you best option is something like below:
Create a table value function that accepts your ranges an converts them to a collection of ints. So 1-3,5 would return:
1
2
3
5
Then use these results to join to other tables. I don't have an exact function to do this at hand, but this one seems like an excellent start.

SQL Select where id is in `column`

I have a column that has multiple numbers separated by a comma. Example for a row:
`numbers`:
1,2,6,66,4,9
I want to make a query that will select the row only if the number 6 (for example) is in the column numbers.
I cant use LIKE because if there is 66 it'll work too.

You can use like. Concatenate the field separators at the beginning and end of the list and then use like. Here is the SQL Server sytnax:
where ','+numbers+',' like '%,'+'6'+',%'
SQL Server uses + for string concatenation. Other databases use || or the concat() function.

You should change your database to rather have a new table that joins numbers with the row of your current table. So if your row looks like this:
id numbers
1 1,2,6,66,4,9
You would have a new table that joins those values like so
row_id number
1 1
1 2
1 6
1 66
1 4
1 9
Then you can search for the number 6 in the number column and get the row_id