foxpro double data type precision - visual-foxpro

I have a table that has numeric columns that are double data type with 2 decimals. We are migrating the data to a new system and noticed that the totals after migration didn't match. It seems that data is being stored beyond the hundredths place. How is that possible with double(2)?
Shouldn't something like this return 0.00?
CREATE CURSOR temp ( fld_dbl2 b(2))
FOR n=1 TO 1000
APPEND BLANK
replace fld_dbl2 WITH RAND()/1000
ENDFOR
SELECT SUM(fld_dbl2) FROM temp
into cursor _csrTemp

From the VFP 9 help file:
When the Double data type is used in a table, the number of decimals
specified when the field is created is for display purposes only.
Visual FoxPro stores the actual value in the field.

Related

Import blob through SAS from ORACLE DB

Good time of a day to everyone.
I face with a huge problem during my work on previous week.
Here ia the deal:
I need to download exel file (blob) from ORACLE database through SAS.
I am using:
First step i need to get data from oracle. I used the construction (blob file is nearly 100kb):
proc sql;
connect to oracle;
create table SASTBL as
select * from connection to oracle (
select dbms_lob.substr(myblobfield,1,32767) as blob_1,
dbms_lob.substr(myblobfield,32768,32767) as blob_2,
dbms_lob.substr(myblobfield,65535,32767) as blob_3,
dbms_lob.substr(myblobfield,97302,32767) as blob_4
from my_tbl;
);
quit;
And the result is:
blob_1 = 70020202020202...02
blob_2 = 02020202020...02
blob_3 = 02020202...02
I do not understand why the field consists from "02"(the whole file)
And the length of any variable in sas is 1024 (instead of 37767) $HEX2024 format.
If I ll take:
dbms_lob.substr(my_blob_field,2000,900) from the same object the result will mush more similar to the truth:
blob = "A234ABC4536AE7...."
The question is: 1. how can i get binary data from blob field correctly trough SAS? What is my mistake?
Thank you.
EDIT 1:
I get the information but max string is 2000 kb.
Use the DBMAX_TEXT option on the CONNECT statement (or a LIBNAME statement) to get up to 32,767 characters. The default is probably 1024.
PROC SQL uses SQL to interact with SAS datasets (create tables, query tables, aggregate data, connect externally, etc.). The procedure mostly follows the ANSI standard with a few SAS specific extensions. Each RDMS extends ANSI including Oracle with its XML handling such as saving content in a blob column. Possibly, SAS cannot properly read the Oracle-specific (non-ANSI) binary large object type. Typically SAS processes string, numeric, datetime, and few other types.
As an alternative, consider saving XML content from Oracle externally as an .xml file and use SAS's XML engine to read content into SAS dataset:
** STORING XML CONTENT;
libname tempdata xml 'C:\Path\To\XML\File.xml';
** APPEND CONTENT TO SAS DATASET;
data Work.XMLData;
set tempdata.NodeName; /* CHANGE TO REPEAT PARENT NODE OF XML. */
run;
Adding as another answer as I can't comment yet... the issue you experienced is that the return of dbms_lob.substr is actually a varchar so SAS limits it to 2,000. To avoid this, you could wrap it in to_clob( ... ) AND set the DBMAX_TEXT option as previously answered.
Another alternative is below...
The code below is an effective method for retrieving a single record with a large CLOB. Instead of calculating how many fields to split the clob into resulting in a very wide record, it instead splits it into multiple rows. See expected output at bottom.
Disclaimer: Although effective it may not be efficient ie may not scale well to multiple rows, the generally accepted approach then is row pipelining PLSQL. That being said, the below got me out of a pinch if you can't make a procedure...
PROC SQL;
connect to oracle (authdomain=YOUR_Auth path=devdb DBMAX_TEXT=32767 );
create table clob_chunks (compress=yes) as
select *
from connection to Oracle (
SELECT id
, key
, level clob_order
, regexp_substr(clob_value, '.{1,32767}', 1, level, 'n') clob_chunk
FROM (
SELECT id, key, clob_value
FROM schema.table
WHERE id = 123
)
CONNECT BY LEVEL <= regexp_count(clob_value, '.{1,32767}',1,'n')
)
order by id, key, clob_order;
disconnect from oracle;
QUIT;
Expected output:
ID KEY CHUNK CLOB
1 1 1 short_clob
2 2 1 long clob chunk1of3
2 2 2 long clob chunk2of3
2 2 3 long clob chunk3of3
3 3 1 another_short_one
Explanation:
DBMAX_TEXT tells SAS to adjust the default of 1024 for a clob field.
The regex .{1,32767} tells Oracle to match at least once but no more than 32767 times. This splits the input and captures the last chunk which is likely to be under 32767 in length.
The regexp_substr is pulling a chunk from the clob (param1) starting from the start of the clob (param2), skipping to the 'level'th occurance (param3) and treating the clob as one large string (param4 'n').
The connect by re-runs the regex to count the chunks to stop the level incrementing beyond end of the clob.
References:
SAS KB article for DBMAX_TEXT
Oracle docs for REGEXP_COUNT
Oracle docs for REGEXP_SUBSTR
Oracle regex syntax
Stackoverflow example of regex splitting

SQLPLUS displaying of tables with CLOB types

I have a table which has 3 columns. I have a NUMBER column, CLOB column, and BLOB column. how can i use some sort of SELECT * statement in order to display what I have entered into this table, not just a partial piece of the long character strings i have in there. The only way I know of displaying a long string form a CLOB would be using the DBMS_LOB.substr technique. My BLOB column is currently all NULL so not too worried about displaying that section, Just the number column with its associated CLOB. Thanks!
See here How to query a CLOB column in Oracle
When getting the substring of a CLOB column and using a query tool that has size/buffer restrictions
sometimes you would need to set the BUFFER to a larger size.
For example while using SQL Plus use the SET BUFFER 10000 to set it to 10000 as the default is 4000.
Running the DMBS_LOB.substr command you can also specify the amount of characters you want to return and the offset from which.
So using DMBS_LOB.substr(column, 3000) might restrict it to a small enough amount for the buffer.
See oracle documentation for more info on the substr command
DBMS_LOB.SUBSTR (
lob_loc IN CLOB CHARACTER SET ANY_CS,
amount IN INTEGER := 32767,
offset IN INTEGER := 1)
RETURN VARCHAR2 CHARACTER SET lob_loc%CHARSET;

How MAX of a concatenated column in oracle works?

In Oracle, while trying to concatenate two columns of both Number type and then trying to take MAX of it, I am having a question.
i.e column A column B of Number data type,
Select MAX(A||B) from table
Table data
A B
20150501 95906
20150501 161938
when I’m running the query Select MAX(A||B) from table
O/P - 2015050195906
Ideally 20150501161938 should be the output????
I am trying to format column B like TO_CHAR(B,'FM000000') and execute i'm getting the expected output.
Select MAX(A || TO_CHAR(B,'FM000000')) FROM table
O/P - 2015011161938
Why is 2015050195906 is considered as MAX in first case.
Presumably, column A is a date and column B is a time.
If that's true, treat them as such:
select max(to_date(to_char(a)||to_char(b,'FM000000'),'YYYYMMDDHH24MISS')) from your_table;
That will add a leading space for the time component (if necessary) then concatenate the columns into a string, which is then passed to the to_date function, and then the max function will treat as a DATE datatype, which is presumably what you want.
PS: The real solution here, is to fix your data model. Don't store dates and times as numbers. In addition to sorting issues like this, the optimizer can get confused. (If you store a date as a number, how can the optimizer know that '20141231' will immediately be followed by '20150101'?)
You should convert to number;
select MAX(TO_NUMBER(A||B)) from table
Concatenation will result in a character/text output. As such, it sorts alphabetically, so 9 appears after 16.
In the second case, you are specifiying a format to pad the number to six digits. That works well, because 095906 will now appear before 161938.

While exporting data from Oracle PLSQL to Excel, format issue is coming

I am trying to export data from Oracle PLSQL to Excel.
The data type of one of the column is VARCHAR2.
The Column conatins value like 00798019859217.
But after exporting, the value in excel is something like this 7.9802E+11.
PLease let me know how to resolve this and the reason for this format issue.
Thanks in advance.
Do the following:
Select the column with single quotes, say
SELECT ("'" || COLUMN_NAME) AS COLUMN_NAME, OTHER_COLUMNS FROM MY_TABLE
Output will be like:
'ABC0157976
'00798019859217
Export the output to an excel.In excel "A" column values will be
'ABC0157976
00798019859217 (Single quote will not be visible for number only values)
Select the entire "A" row and clear all single quotes with replace all option. You will get final excel as.
ABC0157976
00798019859217
Since it is a text field and non-numeric characters are also expected to be present, the step#3 is required. If it is going to be only numeric characters, then step #3 can be ignored.
This is happening due to excel where the number auto casted. As #HamidP said try exporting as csv and check with opening in notepad or text, and check whether the number displaying fully or not. If so then you can open the same in Excel with small options change such
Right click the cell and click format option and make it cell format as text and then save the excel.

PL/SQL code Template

I want to convert a 9 digit number to 10 digit by appending a 0 to it.
For example In Table ABC say there is a column named B which takes a number which is at the max 10 digit long.
Now sometimes I will get a 9 digit number only.
So in that case when a 9 digit number is faced i need to fire a trigger to make it 10 digit and then insert in the table.
For that you need to create the column with character datatype so that it can hold the leading zeros.
You don't need to write any trigger for this simple operation. you can use lpad for this purpose:
eg.g
Insert into table1(number_col) values ( lpad(999999999, 10, '0'));
select * from table1;
| number_col |
|-----------------|
| 0999999999 |
To use this in trigger, create a trigger as follows (Not Tested);
create or replace trigger trg_table1
before insert or update of number_col on table1
for each row
begin
:new.number_col := lpad( :new.number_col, 10, '0' );
end;
You don't really need to make this a trigger. Adding a 0 to the front of the number is really only for humans, the computer doesn't care and that information can't be stored in the database unless you convert the column to a string format.
What you're looking for is one of three things: Either, change the way your forms display the information to add padding if the number is less 10,000,000,000 to affect the way the user sees the information (most recommended)
Or, use the lpad function to convert the number to a string with 0 padding if necessary
lpad(input,10,'0')
Note that this will require conversion back to a number to insert into the DB if it is possible for the user to edit this number. (second most recommended)
Lastly, you can always store the value in a string format and use lpad as above on insert.
I wouldn't recommend this as strings take up much more space than numbers, and the db won't search them as fast. Also, why store a number as a string purely for the user's sake, when you can change the way your data looks to the user programatically?

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