psql expanded display - avoid dashes - postgresql

When I have a very wide column (like a json document) and I am using expanded display to make the contents at least partly readable, I am still seeing extremely ugly record separators, that seems to want to be as wide as the widest column, like so:
Is there a way to avoid the "Sea of Dashes"?
-[ RECORD 1 ]--+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
id | 18
description | {json data xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
parameter | {json data xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
name | Foo
-[ RECORD 2 ]--+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
id | 19
description | {}
parameter | {json data xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
name | CustomerRequestEventType

to avoid sea of dashes, use \pset format unaligned, eg:
t=# \x
Expanded display is on.
t=# \pset format unaligned
Output format is unaligned.
t=# with ts as (select generate_series('2010-01-01'::timestamp,'2010-01-10'::timestamp,'1 day'::interval) s) select array_agg(s) from ts; array_agg|{"2010-01-01 00:00:00","2010-01-02 00:00:00","2010-01-03 00:00:00","2010-01-04 00:00:00","2010-01-05 00:00:00","2010-01-06 00:00:00","2010-01-07 00:00:00","2010-01-08 00:00:00","2010-01-09 00:00:00","2010-01-10 00:00:00"}
Time: 0.250 ms
As you can see, no dashes, but the long string is still wrapped over lines by the length of the window (or not wrapped at all). In case of unformatted string this is the solution, but you mentioned json - it can be devided in a pretty way. To do so instead of using unaligned format in psql, consume jsonb_pretty function or pretty flag of other functions, eg (with array_to_json(..., true):
t=# with ts as (select generate_series('2010-01-01'::timestamp,'2010-01-31'::timestamp,'1 day'::interval) s) select array_to_json(array_agg(s),true) from ts;
array_to_json|["2010-01-01T00:00:00",
"2010-01-02T00:00:00",
"2010-01-03T00:00:00",
"2010-01-04T00:00:00",
"2010-01-05T00:00:00",
"2010-01-06T00:00:00",
"2010-01-07T00:00:00",
"2010-01-08T00:00:00",
"2010-01-09T00:00:00",
"2010-01-10T00:00:00",
"2010-01-11T00:00:00",
"2010-01-12T00:00:00",
"2010-01-13T00:00:00",
"2010-01-14T00:00:00",
"2010-01-15T00:00:00",
"2010-01-16T00:00:00",
"2010-01-17T00:00:00",
"2010-01-18T00:00:00",
"2010-01-19T00:00:00",
"2010-01-20T00:00:00",
"2010-01-21T00:00:00",
"2010-01-22T00:00:00",
"2010-01-23T00:00:00",
"2010-01-24T00:00:00",
"2010-01-25T00:00:00",
"2010-01-26T00:00:00",
"2010-01-27T00:00:00",
"2010-01-28T00:00:00",
"2010-01-29T00:00:00",
"2010-01-30T00:00:00",
"2010-01-31T00:00:00"]
Time: 0.291 ms
Note I still use unaligned format to avoid "+" though...

Related

Postgres full text search and spelling mistakes (aka fuzzy full text search)

I have a scenario, where I have data for informal communications that I need to be able to search. Therefore I want full text search, but I also to make sense of spelling mistakes. Question is how do I take spelling mistakes into account in order to be able to do fuzzy full text search??
This is very briefly discussed in Postgres Full Text Search is Good Enough where the article discusses misspelling.
So I have built a table of "documents", created indexes etc.
CREATE TABLE data (
id int GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
text TEXT NOT NULL);
I can create an additional column of type tsvector and index accordingly...
alter table data
add column search_index tsvector
generated always as (to_tsvector('english', coalesce(text, '')))
STORED;
create index search_index_idx on data using gin (search_index);
I have for example, some text where the data says "baloon", but someone may search "balloon", so I insert two rows (one deliberately misspelled)...
insert into data (text) values ('baloon');
insert into data (text) values ('balloon');
select * from data;
id | text | search_index
----+---------+--------------
1 | baloon | 'baloon':1
2 | balloon | 'balloon':1
... and perform full text searches against the data...
select * from data where search_index ## plainto_tsquery('balloon');
id | text | search_index
----+---------+--------------
2 | balloon | 'balloon':1
(1 row)
But I don't get back results for the misspelled version "baloon"... So using the suggestion in the linked article I've built a lookup table of all the words in my lexicon as follows...
"you may obtain good results by appending the similar lexeme to your tsquery"
CREATE TABLE data_words AS SELECT word FROM ts_stat('SELECT to_tsvector(''simple'', text) FROM data');
CREATE INDEX data_words_idx ON data_words USING GIN (word gin_trgm_ops);
... and I can search for similar words which may have been misspelled
select word, similarity(word, 'balloon') as similarity from data_words where similarity(word, 'balloon') > 0.4 order by similarity(word, 'balloon');
word | similarity
---------+------------
baloon | 0.6666667
balloon | 1
... but how do I actually include misspelled words in my query?
Isn't this what the article above means?
select plainto_tsquery('balloon' || ' ' || (select string_agg(word, ' ') from data_words where similarity(word, 'balloon') > 0.4));
plainto_tsquery
----------------------------------
'balloon' & 'baloon' & 'balloon'
(1 row)
... plugged into an actual search, and I get no rows!
select * from data where text ## plainto_tsquery('balloon' || ' ' || (select string_agg(word, ' ') from data_words where similarity(word, 'balloon') > 0.4));
select * from data where search_index ## phraseto_tsquery('baloon balloon'); -- no rows returned
I'm not sure where I'm going wrong here - can any shed any light? I feel like I'm super close to getting this going...?
SELECT to_tsquery('balloon |' ||
string_agg(word, ' | ')
)
FROM data_words
WHERE similarity(word, 'balloon') > 0.4;
For anyone looking at this thread, the accepted answer by #laurenz-albe needed a slight modification for me:
It required single quotes around the argument values passed to the string_agg function, which can be done using the format function along with the %L placeholder.
This updated code worked for me:
SELECT to_tsquery('balloon |' ||
string_agg(format('%L', word), ' | ')
)
FROM data_words
WHERE similarity(word, 'balloon') > 0.4;

postgresql + textsearch + german umlauts + UTF8

I'm really at my wits end, with this Problem, and I really hope someone could help me. I am using a Postgresql 9.3. My Database contains mostly german texts but not only, so it's encoded in utf-8. I want to establish a fulltextsearch wich supports german language, nothing special so far.
But the search is behaving really strange,, and I can't find out what I am doing wrong.
So, given the following table given as example
select * from test;
a
-------------
ein Baum
viele Bäume
Überleben
Tisch
Tische
Café
\d test
Tabelle »public.test«
Spalte | Typ | Attribute
--------+------+-----------
a | text |
sintext=# \d
Liste der Relationen
Schema | Name | Typ | Eigentümer
--------+---------------------+---------+------------
(...)
public | test | Tabelle | paf
Now, lets have a look at some textsearch examples:
select * from test where to_tsvector('german', a) ## plainto_tsquery('Baum');
a
-------------
ein Baum
viele Bäume
select * from test where to_tsvector('german', a) ## plainto_tsquery('Bäume');
--> No Hits
select * from test where to_tsvector('german', a) ## plainto_tsquery('Überleben');
--> No Hits
select * from test where to_tsvector('german', a) ## plainto_tsquery('Tisch');
a
--------
Tisch
Tische
Whereas Tische is Plural of Tisch (table) and Bäume is plural of Baum (tree). So, Obviously Umlauts does not work while textsearch perfoms well.
But what really confuses me is, that a) non-german special characters are matching
select * from test where to_tsvector('german', a) ## plainto_tsquery('Café');
a
------
Café
and b) if I don't use the german dictionary, there is no Problem with umlauts (but of course no real textsearch as well)
select * from test where to_tsvector(a) ## plainto_tsquery('Bäume');
a
-------------
viele Bäume
So, if I use the german dictionary for Text-Search, just the german special characters do not work? Seriously? What the hell is wrong here? I Really can't figure it out, please help!
You're explicitly using the German dictionary for the to_tsvector calls, but not for the to_tsquery or plainto_tsquery calls. Presumably your default dictionary isn't set to german; check with SHOW default_text_search_config.
Compare:
regress=> select plainto_tsquery('simple', 'Bäume'),
plainto_tsquery('english','Bäume'),
plainto_tsquery('german', 'Bäume');
plainto_tsquery | plainto_tsquery | plainto_tsquery
-----------------+-----------------+-----------------
'bäume' | 'bäume' | 'baum'
(1 row)
The language setting affects word simplification and root extraction, so a vector from one language won't necessarily match a query from another:
regress=> SELECT to_tsvector('german', 'viele Bäume'), plainto_tsquery('Bäume'),
to_tsvector('german', 'viele Bäume') ## plainto_tsquery('Bäume');
to_tsvector | plainto_tsquery | ?column?
-------------------+-----------------+----------
'baum':2 'viel':1 | 'bäume' | f
(1 row)
If you use a consistent language setting, all is well:
regress=> SELECT to_tsvector('german', 'viele Bäume'), plainto_tsquery('german', 'Bäume'),
to_tsvector('german', 'viele Bäume') ## plainto_tsquery('german', 'Bäume');
to_tsvector | plainto_tsquery | ?column?
-------------------+-----------------+----------
'baum':2 'viel':1 | 'baum' | t
(1 row)

Inserting values into multiple columns by splitting a string in PostgreSQL

I have the following heap of text:
"BundleSize,155648,DynamicSize,204800,Identifier,com.URLConnectionSample,Name,
URLConnectionSample,ShortVersion,1.0,Version,1.0,BundleSize,155648,DynamicSize,
16384,Identifier,com.IdentifierForVendor3,Name,IdentifierForVendor3,ShortVersion,
1.0,Version,1.0,".
What I'd like to do is extract data from this in the following manner:
BundleSize:155648
DynamicSize:204800
Identifier:com.URLConnectionSample
Name:URLConnectionSample
ShortVersion:1.0
Version:1.0
BundleSize:155648
DynamicSize:16384
Identifier:com.IdentifierForVendor3
Name:IdentifierForVendor3
ShortVersion:1.0
Version:1.0
All tips and suggestions are welcome.
It isn't quite clear what do you need to do with this data. If you really need to process it entirely in the database (looks like the task for your favorite scripting language instead), one option is to use hstore.
Converting records one by one is easy:
Assuming
%s =
BundleSize,155648,DynamicSize,204800,Identifier,com.URLConnectionSample,Name,URLConnectionSample,ShortVersion,1.0,Version,1.0
SELECT * FROM each(hstore(string_to_array(%s, ',')));
Output:
key | value
--------------+-------------------------
Name | URLConnectionSample
Version | 1.0
BundleSize | 155648
Identifier | com.URLConnectionSample
DynamicSize | 204800
ShortVersion | 1.0
If you have table with columns exactly matching field names (note the quotes, populate_record is case-sensitive to key names):
CREATE TABLE data (
"BundleSize" integer, "DynamicSize" integer, "Identifier" text,
"Name" text, "ShortVersion" text, "Version" text);
You can insert hstore records into it like this:
INSERT INTO data SELECT * FROM
populate_record(NULL::data, hstore(string_to_array(%s, ',')));
Things get more complicated if you have comma-separated values for more than one record.
%s = BundleSize,155648,DynamicSize,204800,Identifier,com.URLConnectionSample,Name,URLConnectionSample,ShortVersion,1.0,Version,1.0,BundleSize,155648,DynamicSize,16384,Identifier,com.IdentifierForVendor3,Name,IdentifierForVendor3,ShortVersion,1.0,Version,1.0,
You need to break up an array into chunks of number_of_fields * 2 = 12 elements first.
SELECT hstore(row) FROM (
SELECT array_agg(str) AS row FROM (
SELECT str, row_number() OVER () AS i FROM
unnest(string_to_array(%s, ',')) AS str
) AS str_sub
GROUP BY (i - 1) / 12) AS row_sub
WHERE array_length(row, 1) = 12;
Output:
"Name"=>"URLConnectionSample", "Version"=>"1.0", "BundleSize"=>"155648", "Identifier"=>"com.URLConnectionSample", "DynamicSize"=>"204800", "ShortVersion"=>"1.0"
"Name"=>"IdentifierForVendor3", "Version"=>"1.0", "BundleSize"=>"155648", "Identifier"=>"com.IdentifierForVendor3", "DynamicSize"=>"16384", "ShortVersion"=>"1.0"
And inserting this into the aforementioned table:
INSERT INTO data SELECT (populate_record(NULL::data, hstore(row))).* FROM ...
the rest of the query is the same.

Split a string and populate a table for all records in table in SQL Server 2008 R2

I have a table EmployeeMoves:
| EmployeeID | CityIDs
+------------------------------
| 24 | 23,21,22
| 25 | 25,12,14
| 29 | 1,2,5
| 31 | 7
| 55 | 11,34
| 60 | 7,9,21,23,30
I'm trying to figure out how to expand the comma-delimited values from the EmployeeMoves.CityIDs column to populate an EmployeeCities table, which should look like this:
| EmployeeID | CityID
+------------------------------
| 24 | 23
| 24 | 21
| 24 | 22
| 25 | 25
| 25 | 12
| 25 | 14
| ... and so on
I already have a function called SplitADelimitedList that splits a comma-delimited list of integers into a rowset. It takes the delimited list as a parameter. The SQL below will give me a table with split values under the column Value:
select value from dbo.SplitADelimitedList ('23,21,1,4');
| Value
+-----------
| 23
| 21
| 1
| 4
The question is: How do I populate EmployeeCities from EmployeeMoves with a single (even if complex) SQL statement using the comma-delimited list of CityIDs from each row in the EmployeeMoves table, but without any cursors or looping in T-SQL? I could have 100 records in the EmployeeMoves table for 100 different employees.
This is how I tried to solve this problem. It seems to work and is very quick in performance.
INSERT INTO EmployeeCities
SELECT
em.EmployeeID,
c.Value
FROM EmployeeMoves em
CROSS APPLY dbo.SplitADelimitedList(em.CityIDs) c;
UPDATE 1:
This update provides the definition of the user-defined function dbo.SplitADelimitedList. This function is used in above query to split a comma-delimited list to table of integer values.
CREATE FUNCTION dbo.fn_SplitADelimitedList1
(
#String NVARCHAR(MAX)
)
RETURNS #SplittedValues TABLE(
Value INT
)
AS
BEGIN
DECLARE #SplitLength INT
DECLARE #Delimiter VARCHAR(10)
SET #Delimiter = ',' --set this to the delimiter you are using
WHILE len(#String) > 0
BEGIN
SELECT #SplitLength = (CASE charindex(#Delimiter, #String)
WHEN 0 THEN
datalength(#String) / 2
ELSE
charindex(#Delimiter, #String) - 1
END)
INSERT INTO #SplittedValues
SELECT cast(substring(#String, 1, #SplitLength) AS INTEGER)
WHERE
ltrim(rtrim(isnull(substring(#String, 1, #SplitLength), ''))) <> '';
SELECT #String = (CASE ((datalength(#String) / 2) - #SplitLength)
WHEN 0 THEN
''
ELSE
right(#String, (datalength(#String) / 2) - #SplitLength - 1)
END)
END
RETURN
END
Preface
This is not the right way to do it. You shouldn't create comma-delimited lists in SQL Server. This violates first normal form, which should sound like an unbelievably vile expletive to you.
It is trivial for a client-side application to select rows of employees and related cities and display this as a comma-separated list. It shouldn't be done in the database. Please do everything you can to avoid this kind of construction in the future. If at all possible, you should refactor your database.
The Right Answer
To get the list of cities, properly expanded, from a table containing lists of cities, you can do this:
INSERT dbo.EmployeeCities
SELECT
M.EmployeeID,
C.CityID
FROM
EmployeeMoves M
CROSS APPLY dbo.SplitADelimitedList(M.CityIDs) C
;
The Wrong Answer
I wrote this answer due to a misunderstanding of what you wanted: I thought you were trying to query against properly-stored data to produce a list of comma-separated CityIDs. But I realize now you wanted the reverse: to query the list of cities using existing comma-separated values already stored in a column.
WITH EmployeeData AS (
SELECT
M.EmployeeID,
M.CityID
FROM
dbo.SplitADelimitedList ('23,21,1,4') C
INNER JOIN dbo.EmployeeMoves M
ON Convert(int, C.Value) = M.CityID
)
SELECT
E.EmployeeID,
CityIDs = Substring((
SELECT ',' + Convert(varchar(max), CityID)
FROM EmployeeData C
WHERE E.EmployeeID = C.EmployeeID
FOR XML PATH (''), TYPE
).value('.[1]', 'varchar(max)'), 2, 2147483647)
FROM
(SELECT DISTINCT EmployeeID FROM EmployeeData) E
;
Part of my difficulty in understanding is that your question is a bit disorganized. Next time, please clearly label your example data and show what you have, and what you're trying to work toward. Since you put the data for EmployeeCities last, it looked like it was what you were trying to achieve. It's not a good use of people's time when questions are not laid out well.

How do you exclude a column from showing up if there is no value?

Question about a query I'm trying to write in SQL Server Management Studio 2008. I am pulling 2 rows. The first row being the header information, the second row being the information for a certain Line Item. Keep in mind, the actual header information reads as "Column 0, 1, 2, 3, 4,.... etc."
The data looks something like this:
ROW 1: Model # | Item Description| XS | S | M | L | XL|
ROW 2: 3241 | Gray Sweatshirt| | 20 | 20 | 30 | |
Basically this shows that there are 20 smalls, 20 mediums, and 30 larges of this particular item. There are no XS's or XL's.
I want to create a subquery that puts this information in one row, but at the same time, disinclude the sizes with a blank quantity amount as shown under the XS and XL sizes.
I want it to look like this when all is said and done:
ROW 1: MODEL #| 3241 | ITEM DESCRIPTION | Gray Sweatshirt | S | 10 | M | 20 | L | 30 |
Notice there are no XS or XL's included. How do I do make it so those columns do not appear?
Since you are not posting your query, nor your table structure, I guess it is with columns Id, Description, Size. If so, you could do this and just replace with your table and column names:
DECLARE #columns varchar(8000)
SELECT #columns = COALESCE (#columns + ',[' + cast(Size as varchar) + ']', '[' + cast(Size as varchar) + ']' )
FROM YourTableName
WHERE COUNT(Size) > 0
DECLARE #query varchar(8000) = 'SELECT Id, Description, '
+ #columns +'
FROM
(SELECT Id, Description, Size
FROM YourTableName) AS Source
PIVOT
(
COUNT(Size)
FOR Size IN ('+ #columns +')
) AS Pvt'
EXEC(#query)
Anyhow, I also agree with #MichaelFredickson. I have implemented this pivot solution, yet it is absolutely better to let the presentation layer to take care of this after just pulling the raw data from SQL. If not, you would be processing the data twice, one on SQL to create the table and the other in the presentation when reading and displaying the values with your c#/vb/other code.