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I need to create an Oracle DB function that takes a string as parameter. The string contains letters and numbers. I need to extract all the numbers from this string. For example, if I have a string like RO1234, I need to be able to use a function, say extract_number('RO1234'), and the result would be 1234.
To be even more precise, this is the kind of SQL query which this function would be used in.
SELECT DISTINCT column_name, extract_number(column_name)
FROM table_name
WHERE extract_number(column_name) = 1234;
QUESTION: How do I add a function like that to my Oracle database, in order to be able to use it like in the example above, using any of Oracle SQL Developer or SQLTools client applications?
You'd use REGEXP_REPLACE in order to remove all non-digit characters from a string:
select regexp_replace(column_name, '[^0-9]', '')
from mytable;
or
select regexp_replace(column_name, '[^[:digit:]]', '')
from mytable;
Of course you can write a function extract_number. It seems a bit like overkill though, to write a funtion that consists of only one function call itself.
create function extract_number(in_number varchar2) return varchar2 is
begin
return regexp_replace(in_number, '[^[:digit:]]', '');
end;
You can use regular expressions for extracting the number from string. Lets check it. Suppose this is the string mixing text and numbers 'stack12345overflow569'. This one should work:
select regexp_replace('stack12345overflow569', '[[:alpha:]]|_') as numbers from dual;
which will return "12345569".
also you can use this one:
select regexp_replace('stack12345overflow569', '[^0-9]', '') as numbers,
regexp_replace('Stack12345OverFlow569', '[^a-z and ^A-Z]', '') as characters
from dual
which will return "12345569" for numbers and "StackOverFlow" for characters.
This works for me, I only need first numbers in string:
TO_NUMBER(regexp_substr(h.HIST_OBSE, '\.*[[:digit:]]+\.*[[:digit:]]*'))
the field had the following string: "(43 Paginas) REGLAS DE PARTICIPACION".
result field: 43
If you are looking for 1st Number with decimal as string has correct decimal places, you may try regexp_substr function like this:
regexp_substr('stack12.345overflow', '\.*[[:digit:]]+\.*[[:digit:]]*')
To extract charecters from a string
SELECT REGEXP_REPLACE(column_name,'[^[:alpha:]]') alpha FROM DUAL
In order to extract month and a year from a string 'A0807' I did the following in PL/SQL:
DECLARE
lv_promo_code VARCHAR2(10) := 'A0807X';
lv_promo_num VARCHAR2(5);
lv_promo_month NUMBER(4);
lv_promo_year NUMBER(4);
BEGIN
lv_promo_num := REGEXP_SUBSTR(lv_promo_code, '(\d)(\d)(\d)(\d)');
lv_promo_month := EXTRACT(month from to_date(lv_promo_num, 'MMYY'));
DBMS_OUTPUT.PUT_LINE(lv_promo_month);
lv_promo_year := EXTRACT(year from to_date(lv_promo_num, 'MMYY'));
DBMS_OUTPUT.PUT_LINE(lv_promo_year);
END;
Note: I cant change the datatype of column
I want to store a character into a table that has column with number datatype.
The work around i found is convert the character values to ASCII and when retrieving it from the database convert it back to character.
I used couple of function ASCII and ASCIISTR but the limitation with these functions are they are converting only first character of the string.
So i used dump function
select dump('Puneet_kushwah1') from dual;
Result: Typ=96 Len=15: 80,117,110,101,101,116,95,107,117,115,104,119,97,104,49
This function is giving ASCII value of all the characters. Then i execute below query
select replace(substr((DUMP('Puneet_kushwah1')),(instr(DUMP('Puneet_kushwah1'),':')+2 )),',',' ') from dual;
Result: 80 117 110 101 101 116 95 107 117 115 104 119 97 104 49
then i used a special character to fill the space, so that i can replace it while retrieving from the database.
select replace(substr((DUMP('Puneet_kushwah1')),(instr(DUMP('Puneet_kushwah1'),':')+2 )),',','040') from dual;
Result: 80040117040110040101040101040116040950401070401170401150401040401190409704010404049
Table definition:
create table test (no number);
Then i inserted it into the table
INSERT into test SELECT replace(substr((DUMP('Puneet_kushwah1')),(instr(DUMP('Puneet_kushwah1'),':')+2 )),',','040') from dual;
Problem 1:
When i execute
select * from test;
i got
Result: 8.004011704011E82
I want to convert it into number only. Exact same what i inserted.
Problem 2:
And then when i execute select i want it to return the exact character string.
Please help i tried many functions.
Thanks in advance.
You can't get the exact string back because Oracle numbers are only stored up to 38 digits of precision.
So if you run this:
select cast(no as varchar2(100))
from test;
You'll get:
80040117040110040101040101040116040950400000000000000000000000000000000000000000000
While I advise not to proceed like this as this could be rife for errors and a possible maintenance nightmare, I do like a challenge and have been forced to do some screwy things myself in order make some vendor's bizarre way of doing things work for us so I sympathize with you if that is the case. So, for the fun of it check this out.
Convert to hex, then to a decimal and insert into the database (x_test has one NUMBER column), then select, converting back:
SQL> insert into x_test
2 select to_number(rawtohex('Puneet_kushwah1'), rpad('X', length(rawtohex('Puneet_kushwah1')), 'X')) from dual;
1 row created.
SQL> select * from x_test;
col1
----------
4.1777E+35
SQL> SELECT utl_raw.cast_to_varchar2(hextoraw(trim(to_char(col1, 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'))))
2 FROM x_test;
UTL_RAW.CAST_TO_VARCHAR2(HEXTORAW(TRIM(TO_CHAR(col1,'XXXXXXXXXXXXXXXXXXXXXXXXXXXX
--------------------------------------------------------------------------------
Puneet_kushwah1
SQL>
While it's a horrible idea and a horrible data model, you could convert some strings into numbers by converting their raw representation into a number:
create or replace function string_to_number(p_string varchar2)
return number as
l_raw raw(40);
l_number number;
begin
l_raw := utl_i18n.string_to_raw(data => p_string, dst_charset => 'AL32UTF8');
l_number := to_number(rawtohex(l_raw), 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx');
return l_number;
end;
/
And back again:
create or replace function number_to_string(p_number number)
return varchar2 as
l_raw raw(40);
l_string varchar2(20);
begin
l_raw := hextoraw(to_char(p_number, 'fmxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'));
l_string := utl_i18n.raw_to_char(data => l_raw, src_charset => 'AL32UTF8');
return l_string;
end;
/
Which you could use as:
insert into test (no) values (string_to_number('Puneet_kushwah1'));
1 row inserted.
select * from test;
NO
---------------------------------------
417765537084927079232028220523112497
select number_to_string(no) from test;
NUMBER_TO_STRING(NO)
--------------------------------------------------------------------------------
Puneet_kushwah1
You don't really need functions, you could do the conversions in-line; but this makes what's happening a bit clearer.
But you're restricted by the precision of the number type. I think you're limited to about 20 characters, but it'll depend a bit on the actual string and its hex representation.
(I am not endorsing this approach, it's just a mildly interesting problem).
This question already has an answer here:
Oracle - ORA-01489: result of string concatenation is too long [duplicate]
(1 answer)
Closed 7 years ago.
Select TO_CLOB(a)|| TO_CLOB(b)|| TO_CLOB(c) || TO_CLOB(d)
from table1
Above query is not spooling the data properly into text file.
whereas,
Select a||b||c||d
from table1.
is ending to
ERROR at line 191: ORA-01489: result of string concatenation is too long.
Please help !!!
VARCHAR2 are limited to 4000 bytes. If you get this error
ERROR at line 191: ORA-01489: result of string concatenation is too
long.
Then it is pretty clear that the concatenation exceed 4000 bytes.
Now what to do ?
Your first solution to use CLOB instead is correct.
select TO_CLOB(a)|| TO_CLOB(b)|| TO_CLOB(c) || TO_CLOB(d)
It seems like your real problem is saving to file
Above query is not spooling the data properly into text file.
While you did not post how to save the resulting clob to a file, I believe you are not doing it correctly. If you try to save to file the same way as you were doing it with VARCHAR2, you are doing it wrong.
You need to first use dbms_lob.read to read the clob from database, then use utl_file.put_raw to write to file.
DECLARE
position NUMBER := 1;
byte_length NUMBER := 32760;
length NUMBER;
vblob BLOB;
rawlob RAW(32760);
temp NUMBER;
output utl_file.file_type;
BEGIN
-- Last parameter is maximum number of bytes returned.
-- wb stands for write byte mode
output := utl_file.fopen('DIR', 'filename', 'wb', 32760);
position := 1;
select dbms_lob.getlength(yourLob)
into len
from somewhere
where something;
temp := length;
select yourLob
into vlob
from somewhere
where something;
IF len < 32760 THEN
utl_file.put_raw(output, vblob);
-- Don't forget to flush
utl_file.fflush(output);
ELSE -- write part by part
WHILE position < len AND byte_length > 0
LOOP
dbms_lob.read(vblob, byte_length, position, rawlob);
utl_file.put_raw(output,rawlob);
-- You must admit, you would have forgot to flush.
utl_file.fflush(output);
position := position + byte_length;
-- set the end position if less than 32000 bytes
temp := temp - bytelen;
IF temp < 32760 THEN
byte_length := temp;
END IF;
END IF;
END;
How about increasing the value for LONG? You might have to increase the long variable to a higher value. Click here for detailed description.
Example:
SET LONG 100000;
SPOOL test_clob.txt
SELECT to_clob(lpad('A',4000,'A'))
||'B'
||to_clob(lpad('C',4000,'C'))
||'D'
||to_clob(lpad('E',4000,'E'))
||'F'
FROM dual;
SPOOL OFF;
Your second query returns error because,
The concat(||) operator in the query is trying to return varchar2, which has limit of 4000 characters and getting exceeded.
SQL*Plus hardcode linesize 81 when displaying CLOB, there seems no way around it. Therefore if you want to generate a csv file to be loaded to other databases, you will have a problem of parsing these extra newlines.
The ultimate solution is to use PL/SQL. For example, to genarate a comma delimited csv file from table "xyz", use the following code:
set lin 32766
set serveroutput on size unlimited
DECLARE
TYPE arraytable IS TABLE OF xyz%ROWTYPE;
myarray arraytable;
CURSOR c IS
select * from xyz ;
BEGIN
OPEN c;
LOOP
FETCH c BULK COLLECT INTO myarray LIMIT 10000;
FOR i IN 1 .. myarray.COUNT
LOOP
DBMS_OUTPUT.PUT_LINE(
myarray(i).col1||','||
myarray(i).col2||','||
myarray(i).col3||','||
myarray(i).col4;
END LOOP;
EXIT WHEN c%NOTFOUND;
END LOOP;
END;
/
A bonus of this approach is that this even works with LONG datatype!
Try xmlagg function. That worked well for me when I encountered a similar issue.
http://docs.oracle.com/cd/B19306_01/server.102/b14200/functions215.htm
Using Postgresql 8.4, how can I right-pad a string with blanks without truncating it when it's too long?
The problem is that rpad truncates the string when it is actually longer than number of characters to pad. Example:
SELECT rpad('foo', 5); ==> 'foo ' -- fine
SELECT rpad('foo', 2); ==> 'fo' -- not good, I want 'foo' instead.
The shortest solution I found doesn't involve rpad at all:
SELECT 'foo' || repeat(' ', 5-length('foo')); ==> 'foo ' -- fine
SELECT 'foo' || repeat(' ', 2-length('foo')); ==> 'foo' -- fine, too
but this looks ugly IMHO. Note that I don't actually select the string 'foo' of course, instead I select from a column:
SELECT colname || repeat(' ', 30-length(colname)) FROM mytable WHERE ...
Is there a more elegant solution?
found a slightly more elegant solution:
SELECT greatest(colname,rpad(colname, 2));
eg:
SELECT greatest('foo',rpad('foo', 5)); -- 'foo '
SELECT greatest('foo',rpad('foo', 2)); -- 'foo'
.
To explain how it works:
rpad('foo',5) = 'foo ' which is > 'foo' (greatest works with strings as well as numbers)
rpad('foo',2) = 'fo' which is < 'foo', so 'foo' is selected by greatest function.
if you want left-padded words you cant use greatest because it compares left-to-right (eg 'oo' with 'foo') and in some cases this will be greater or smaller depending on the string. I suppose you could reverse the string and use the rpad and reverse it back, or just use the original solution which works in both cases.
If you don't want to write that repeat business all the time, just write your own function for it. Something like this:
create or replace function rpad_upto(text, int) returns text as $$
begin
if length($1) >= $2 then
return $1;
end if;
return rpad($1, $2);
end;
$$ language plpgsql;
or this:
create or replace function rpad_upto(text, int) returns text as $$
select $1 || repeat(' ', $2 - length($1));
$$ language sql;
Then you can say things like:
select rpad_upto(colname, 30) from mytable ...
You might want to consider what you want rpad_upto(null, n) to produce while you're at it. Both versions of rpad_upto above will return NULL if $1 is NULL but you can tweak them to return something else without much difficulty.
how about this
select case when length(col) < x then rpad(col, x)
else col
end
from table
Assuming efficiency is not your biggest concern here:
select regexp_replace(format('%5s', 'foo'), '(\s*)(\S*)', '\2\1')
format() left-pads the string to the desired width
then regexp_replace moves any leading spaces to the end.
I guess that would fail if you have leading spaces in the strings and you want to preserve them. Also note that format() doesn't return null on null params.
PostgreSQL statement below is to right pad three place values and alter column data type to text for column 'columnname.' I used pycharm IDE to help construct statement. The statement will pad with 000.
I have been looking for a while to solve the same issue, except for left pad and I thought I would share.
alter table 'schema.tablename' alter column 'columnname' type text using rpad('columnname'::text,3,'0')
I want to use parameter for query like this :
SELECT * FROM MATABLE
WHERE MT_ID IN (368134, 181956)
so I think about this
SELECT * FROM MATABLE
WHERE MT_ID IN (:MYPARAM)
but it doesn't work...
Is there a way to do this ?
I actually use IBX and Firebird 2.1
I don't know how many parameters in IN clause.
For whom ever is still interested. I did it in Firebird 2.5 using another stored procedure inspired by this post.
How to split comma separated string inside stored procedure?
CREATE OR ALTER PROCEDURE SPLIT_STRING (
ainput varchar(8192))
RETURNS (
result varchar(255))
AS
DECLARE variable lastpos integer;
DECLARE variable nextpos integer;
DECLARE variable tempstr varchar(8192);
BEGIN
AINPUT = :AINPUT || ',';
LASTPOS = 1;
NEXTPOS = position(',', :AINPUT, LASTPOS);
WHILE (:NEXTPOS > 1) do
BEGIN
TEMPSTR = substring(:AINPUT from :LASTPOS for :NEXTPOS - :LASTPOS);
RESULT = :TEMPSTR;
LASTPOS = :NEXTPOS + 1;
NEXTPOS = position(',', :AINPUT, LASTPOS);
suspend;
END
END
When you pass the SP the following list
CommaSeperatedList = 1,2,3,4
and call
SELECT * FROM SPLIT_STRING(:CommaSeperatedList)
the result will be :
RESULT
1
2
3
4
And can be used as follows:
SELECT * FROM MyTable where MyKeyField in ( SELECT * FROM SPLIT_STRING(:CommaSeperatedList) )
I ended up using a global temporary table in Firebird, inserting parameter values first and to retrieve results I use a regular JOIN instead of a WHERE ... IN clause. The temporary table is transaction-specific and cleared on commit (ON COMMIT DELETE ROWS).
Maybe you should wite it like this:
SELECT * FROM MATABLE
WHERE MT_ID IN (:MYPARAM1 , :MYPARAM2)
I don't think it's something that can be done. Are there any particular reason why you don't want to build the query yourself?
I've used this method a couple of times, it doesn't use parameters though. It uses a stringlist and it's property DelimitedText. You create a IDList and populate it with your IDs.
Query.SQL.Add(Format('MT_ID IN (%s)', [IDList.DelimitedText]));
You might also be interested in reading the following:
http://www.sommarskog.se/dynamic_sql.html
and
http://www.sommarskog.se/arrays-in-sql-2005.html
Covers dynamic sql with 'in' clauses and all sorts. Very interesting.
Parameters are placeholders for single values, that means that an IN clause, that accepts a comma delimited list of values, cannot be used with parameters.
Think of it this way: wherever I place a value, I can use a parameter.
So, in a clause like: IN (:param)
I can bind the variable to a value, but only 1 value, eg: IN (4)
Now, if you consider an "IN clause value expression", you get a string of values: IN (1, 4, 6) -> that's 3 values with commas between them. That's part of the SQL string, not part of a value, which is why it cannot be bound by a parameter.
Obviously, this is not what you want, but it's the only thing possible with parameters.
The answer from Yurish is a solution in two out of three cases:
if you have a limited number of items to be added to your in clause
or, if you are willing to create parameters on the fly for each needed element (you don't know the number of elements in design time)
But if you want to have arbitrary number of elements, and sometimes no elements at all, then you can generate SLQ statement on the fly. Using format helps.
SELECT * FROM MATABLE
WHERE MT_ID IN (:MYPARAM) instead of using MYPARAM with :, use parameter name.
like SELECT * FROM MATABLE
WHERE MT_ID IN (SELECT REGEXP_SUBSTR(**MYPARAM,'[^,]+', 1, LEVEL)
FROM DUAL
CONNECT BY REGEXP_SUBSTR(MYPARAM, '[^,]+', 1, LEVEL) IS NOT NULL))**
MYPARAM- '368134,181956'
If you are using Oracle, then you should definitely check out Tom Kyte's blog post on exactly this subject (link).
Following Mr Kyte's lead, here is an example:
SELECT *
FROM MATABLE
WHERE MT_ID IN
(SELECT TRIM(substr(text, instr(text, sep, 1, LEVEL) + 1,
instr(text, sep, 1, LEVEL + 1) -
instr(text, sep, 1, LEVEL) - 1)) AS token
FROM (SELECT sep, sep || :myparam || sep AS text
FROM (SELECT ',' AS sep
FROM dual))
CONNECT BY LEVEL <= length(text) - length(REPLACE(text, sep, '')) - 1)
Where you would bind :MYPARAM to '368134,181956' in your case.
Here is a technique I have used in the past to get around that 'IN' statement problem. It builds an 'OR' list based on the amount of values specified with parameters (unique). Then all I had to do was add the parameters in the order they appeared in the supplied value list.
var
FilterValues: TStringList;
i: Integer;
FilterList: String;
Values: String;
FieldName: String;
begin
Query.SQL.Text := 'SELECT * FROM table WHERE '; // set base sql
FieldName := 'some_id'; // field to filter on
Values := '1,4,97'; // list of supplied values in delimited format
FilterList := '';
FilterValues := TStringList.Create; // will get the supplied values so we can loop
try
FilterValues.CommaText := Values;
for i := 0 to FilterValues.Count - 1 do
begin
if FilterList = '' then
FilterList := Format('%s=:param%u', [FieldName, i]) // build the filter list
else
FilterList := Format('%s OR %s=:param%u', [FilterList, FieldName, i]); // and an OR
end;
Query.SQL.Text := Query.SQL.Text + FilterList; // append the OR list to the base sql
// ShowMessage(FilterList); // see what the list looks like.
if Query.ParamCount <> FilterValues.Count then
raise Exception.Create('Param count and Value count differs.'); // check to make sure the supplied values have parameters built for them
for i := 0 to FilterValues.Count - 1 do
begin
Query.Params[i].Value := FilterValues[i]; // now add the values
end;
Query.Open;
finally
FilterValues.Free;
end;
Hope this helps.
There is one trick to use reversed SQL LIKE condition.
You pass the list as string (VARCHAR) parameter like '~12~23~46~567~'
Then u have query like
where ... :List_Param LIKE ('%~' || CAST( NumField AS VARCHAR(20)) || '~%')
CREATE PROCEDURE TRY_LIST (PARAM_LIST VARCHAR(255)) RETURNS (FIELD1....)
AS
BEGIN
/* Check if :PARAM_LIST begins with colon "," and ands with colon ","
the list should look like this --> eg. **",1,3,4,66,778,33,"**
if the format of list is right then GO if not just add then colons
*/
IF (NOT SUBSTRING(:PARAM_LIST FROM 1 FOR 1)=',') THEN PARAM_LIST=','||PARAM_LIST;
IF (NOT SUBSTRING(:PARAM_LIST FROM CHAR_LENGTH(:PARAM_LIST) FOR 1)=',') THEN PARAM_LIST=PARAM_LIST||',';
/* Now you are shure thet :PARAM_LIST format is correct */
/ * NOW ! */
FOR SELECT * FROM MY_TABLE WHERE POSITION(','||MY_FIELD||',' in :PARAM_LIST)>0
INTO :FIELD1, :FIELD2 etc... DO
BEGIN
SUSPEND;
END
END
How to use it.
SELECT * FROM TRY_LIST('3,4,544,87,66,23')
or SELECT * FROM TRY_LIST(',3,4,544,87,66,23,')
if the list have to be longer then 255 characters then just change the part of header f.eg. like PARAM_LIST VARCHAR(4000)