I have a string X-99-XX-999 in postgres 9.6. I'm looking to extract XX. The XX is always between the second and the third hyphen. Can anyone please help?
Use the function split_part()
select split_part('X-99-XX-999', '-', 3)
split_part
------------
XX
(1 row)
From the documentation:
split_part(string text, delimiter text, field int)
Split string on delimiter and return the given field (counting from one)
Related
I am relatively new to PostgreSQL and I know how to pad a number with zeros to the left in SQL Server but I'm struggling to figure this out in PostgreSQL.
I have a number column where the maximum number of digits is 3 and the min is 1: if it's one digit it has two zeros to the left, and if it's 2 digits it has 1, e.g. 001, 058, 123.
In SQL Server I can use the following:
RIGHT('000' + cast([Column1] as varchar(3)), 3) as [Column2]
This does not exist in PostgreSQL. Any help would be appreciated.
You can use the rpad and lpad functions to pad numbers to the right or to the left, respectively. Note that this does not work directly on numbers, so you'll have to use ::char or ::text to cast them:
SELECT RPAD(numcol::text, 3, '0'), -- Zero-pads to the right up to the length of 3
LPAD(numcol::text, 3, '0') -- Zero-pads to the left up to the length of 3
FROM my_table
The to_char() function is there to format numbers:
select to_char(column_1, 'fm000') as column_2
from some_table;
The fm prefix ("fill mode") avoids leading spaces in the resulting varchar. The 000 simply defines the number of digits you want to have.
psql (9.3.5)
Type "help" for help.
postgres=> with sample_numbers (nr) as (
postgres(> values (1),(11),(100)
postgres(> )
postgres-> select to_char(nr, 'fm000')
postgres-> from sample_numbers;
to_char
---------
001
011
100
(3 rows)
postgres=>
For more details on the format picture, please see the manual:
http://www.postgresql.org/docs/current/static/functions-formatting.html
As easy as
SELECT lpad(42::text, 4, '0')
References:
http://www.postgresql.org/docs/current/static/functions-string.html
sqlfiddle: http://sqlfiddle.com/#!15/d41d8/3665
The easiest way:
ltrim(to_char(Column1, '000'))
I have a varchar type where each value looks like
539,000
153,300
55,300
752,500
4410,000
I need change column type with number format
I tried use to_number but it is not working
In case your text representation is a German decimal value (comma is decimal separator):
demo:db<>fiddle
Replace comma with dot and simply cast into float:
SELECT replace('123,456', ',', '.')::float
In case the comma separates the thousand groups you need to use the G formatter, which describes this:
demo:db<>fiddle
SELECT to_number('123,456', 'FM999G999')
FM supresses leading blanks and zeros, so even smaller number would work:
SELECT to_number('56', 'FM999G999')
Make sure you have German numeric configuration set and use to_number:
SHOW lc_numeric;
lc_numeric
------------
de_DE.utf8
(1 row)
SELECT to_number('539,000', '99999D000');
to_number
-----------
539.000
(1 row)
You can alter like this
ALTER COLUMN my_column TYPE float USING replace(my_column, ',','.')::float
https://dbfiddle.uk/?rdbms=postgres_10&fiddle=2ff308849d986d26637a011102bb752c
String contains numeric and alphabetic data. what is the way to pick up only number? for example:
for the string "abc-123a-66" select should return "123"
You could use regexp_matches
CREATE table foo (
test VARCHAR);
INSERT INTO foo VALUES('abc-123a-66');
SELECT (regexp_matches(test, '\d+'))[1] FROM foo;
Example at SQLFiddle
In PostgreSQL this can be done with:
SELECT regexp_matches(regexp_replace(whatever_columnn,'\D*',''),'\d+') FROM whatever_table;
The first function (regexp_replace) deletes every non digit from the beginning of the string, the second (regexp_matches) extracts one or more occurrences of any digit from the output of the first function.
I need to remove non-numeric characters in a column (character varying) and keep numeric values in postgresql 9.3.5.
Examples:
1) "ggg" => ""
2) "3,0 kg" => "3,0"
3) "15 kg." => "15"
4) ...
There are a few problems, some values are like:
1) "2x3,25"
2) "96+109"
3) ...
These need to remain as is (i.e when containing non-numeric characters between numeric characters - do nothing).
Using regexp_replace is more simple:
# select regexp_replace('test1234test45abc', '[^0-9]+', '', 'g');
regexp_replace
----------------
123445
(1 row)
The ^ means not, so any character that is not in the range 0-9 will be replaced with an empty string, ''.
The 'g' is a flag that means all matches will be replaced, not just the first match.
For modifying strings in PostgreSQL take a look at The String functions and operators section of the documentation. Function substring(string from pattern) uses POSIX regular expressions for pattern matching and works well for removing different characters from your string.
(Note that the VALUES clause inside the parentheses is just to provide the example material and you can replace it any SELECT statement or table that provides the data):
SELECT substring(column1 from '(([0-9]+.*)*[0-9]+)'), column1 FROM
(VALUES
('ggg'),
('3,0 kg'),
('15 kg.'),
('2x3,25'),
('96+109')
) strings
The regular expression explained in parts:
[0-9]+ - string has at least one number, example: '789'
[0-9]+.* - string has at least one number followed by something, example: '12smth'
([0-9]+.\*)* - the string similar to the previous line zero or more times, example: '12smth22smth'
(([0-9]+.\*)*[0-9]+) - the string from the previous line zero or more times and at least one number at the end, example: '12smth22smth345'
I want to convert a column of type "character varying" that has integers with commas to a regular integer column.
I want to support numbers from '1' to '10,000,000'.
I've tried to use: to_number(fieldname, '999G999G999'), but it only works if the format matches the exact length of the string.
Is there a way to do this that supports from '1' to '10,000,000'?
select replace(fieldname,',','')::numeric ;
To do it the way you originally attempted, which is not advised:
select to_number( fieldname,
regexp_replace( replace(fieldname,',','G') , '[0-9]' ,'9','g')
);
The inner replace changes commas to G. The outer replace changes numbers to 9. This does not factor in decimal or negative numbers.
You can just strip out the commas with the REPLACE() function:
CREATE TABLE Foo
(
Test NUMERIC
);
insert into Foo VALUES (REPLACE('1,234,567', ',', '')::numeric);
select * from Foo; -- Will show 1234567
You can replace the commas by an empty string as suggested, or you could use to_number with the FM prefix, so the query would look like this:
SELECT to_number(my_column, 'FM99G999G999')
There are things to take note:
When using function REPLACE("fieldName", ',', '') on a table, if there are VIEW using the TABLE, that function will not work properly. You must drop the view to use it.