sql - Reproduce certain rows in PostgreSQL -

-

i have table ids represent individuals (call id_table) , table characteristics individual can have (call char_table).

now want add column id_table containing values char_table. difficulty, me, is, id shall 1 characteristic (simple case) , id shall several characteristics. reason rows these id several characteristics must reproduced until have matched every characteristic id. example: id '001' shall characteristics 'a', 'b', , 'c'. row id='001' must reproduced 2 times (to same row 3 times) , each of these rows shall 1 of these 3 characteristics.

i hope explained intelligible enough. idea how this? thanks.

in cases, want association or junction table. table like:

create table individualcharacteristicsr (     individualid int not null,     characterid int not null );

(it might have unique id itself.)

each characteristic individual has on separate row. so, 3 characteristics mean 3 rows. typical query using information join 3 tables:

from id_table left outer join      individualcharacteristicsr ic      on i.individualid = ic.individualid left outer join      char_table c      on c.characteristicid = ic.characteristicid

(the left outer join includes individuals no characteristics.)

in postgres, store characteristics in string or array. neither convenient joining id_char. better approach additional table.


Comments

Post a Comment

Popular posts from this blog

python - Subclassed QStyledItemDelegate ignores Stylesheet -

-
i'm trying subclass qstyleditemdelegate remove focus rectangle in qcombobox . even though i'm calling base implementation of paint function , nothing else, result different. looks if parts of style-sheet influence bounding box of item taken consideration. class pstyleditemdelegate(qstyleditemdelegate): def __init__(self, *args, **kwds): super(pstyleditemdelegate, self).__init__(*args, **kwds) def paint(self, *args, **kwargs): qstyleditemdelegate.paint(*args, **kwargs) what have paint unmodified qstyleditemdelegate ? as suggested tried replacing pyside pyqt4 , works, appears bug. update pyside 1.1.2 1.2.1 result same. unfortunately switch breaks other parts of code, if there no other suggestions i'm going accept answer. edit bug tracked here
Read more

java - HttpClient 3.1 Connection pooling vs HttpClient 4.3.2 -

-
i have used httpclient3.1(java) connection pooling below : import org.apache.commons.httpclient.httpclient; import org.apache.commons.httpclient.multithreadedhttpconnectionmanager; import org.apache.commons.httpclient.params.httpclientparams; import org.apache.commons.httpclient.params.httpmethodparams; import org.apache.log4j.logger; public class httpclientmanager { private static logger logger = logger.getlogger(httpclientmanager.class); private static multithreadedhttpconnectionmanager connectionmanager = new multithreadedhttpconnectionmanager(); private static httpclientparams clientparams = new httpclientparams(); static { try { clientparams.makelenient(); clientparams.setauthenticationpreemptive(false); clientparams.setparameter(httpmethodparams.so_timeout, new integer(30000)); // set so_timeout clientparams.setparameter(httpmethodparams.head_body_check_timeout, new integer(3000)); // head responses ...
Read more

node.js - StackOverflow API not returning JSON -

-
i using node.js script gather data stackoverflow. know responses gzipped, put code in should take care of that. script follows: var request = require('request'); var zlib = require('zlib'); function getstackoverflowresponse(url, callback){ request(url, {encoding: null}, function(err, response, body){ if(response.headers['content-encoding'] == 'gzip'){ zlib.gunzip(body, function(err, dezipped) { callback(dezipped); }); } else { callback(body); } }); } var url = "https://api.stackexchange.com/docs/questions#pagesize=2&order=desc&min=2014-01-04&max=2014-02-02&sort=activity&tagged=apigee&filter=default&site=stackoverflow&run=true"; getstackoverflowresponse(url, function(questions) { console.log(questions); }); instead of getting json output, i'm getting following response: buffer 0d 0a 0d 0a 0d 0a 0d 0a 3c 21 44 4f 43 54 59 50 45 20 48...
Read more