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  • MySQL query does not return any data

    - by Alex L
    Hi, I need to retrieve data from a specific time period. The query works fine until I specify the time period. Is there something wrong with the way I specify time period? I know there are many entries within that time-frame. This query returns empty: SELECT stop_times.stop_id, STR_TO_DATE(stop_times.arrival_time, '%H:%i:%s') as stopTime, routes.route_short_name, routes.route_long_name, trips.trip_headsign FROM trips JOIN stop_times ON trips.trip_id = stop_times.trip_id JOIN routes ON routes.route_id = trips.route_id WHERE stop_times.stop_id = 5508 HAVING stopTime BETWEEN DATE_SUB(stopTime,INTERVAL 1 MINUTE) AND DATE_ADD(stopTime,INTERVAL 20 MINUTE); Here is it's EXPLAIN: +----+-------------+------------+--------+------------------+---------+---------+-------------------------------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+------------+--------+------------------+---------+---------+-------------------------------+------+-------------+ | 1 | SIMPLE | stop_times | ref | trip_id,stop_id | stop_id | 5 | const | 605 | Using where | | 1 | SIMPLE | trips | eq_ref | PRIMARY,route_id | PRIMARY | 4 | wmata_gtfs.stop_times.trip_id | 1 | | | 1 | SIMPLE | routes | eq_ref | PRIMARY | PRIMARY | 4 | wmata_gtfs.trips.route_id | 1 | | +----+-------------+------------+--------+------------------+---------+---------+-------------------------------+------+-------------+ 3 rows in set (0.00 sec) The query works if I remove the HAVING clause (don't specify time range). Returns: +---------+----------+------------------+-----------------+---------------+ | stop_id | stopTime | route_short_name | route_long_name | trip_headsign | +---------+----------+------------------+-----------------+---------------+ | 5508 | 06:31:00 | "80" | "" | "FORT TOTTEN" | | 5508 | 06:57:00 | "80" | "" | "FORT TOTTEN" | | 5508 | 07:23:00 | "80" | "" | "FORT TOTTEN" | | 5508 | 07:49:00 | "80" | "" | "FORT TOTTEN" | | 5508 | 08:15:00 | "80" | "" | "FORT TOTTEN" | | 5508 | 08:41:00 | "80" | "" | "FORT TOTTEN" | | 5508 | 09:08:00 | "80" | "" | "FORT TOTTEN" | I am using Google Transit format Data loaded into MySQL. The query is supposed to provide stop times and bus routes for a given bus stop. For a bus stop, I am trying to get: Route Name Bus Name Bus Direction (headsign) Stop time The results should be limited only to buses times from 1 min ago to 20 min from now. Please let me know if you could help.

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  • Getting wierd issue with TO_NUMBER function in Oracle

    - by Fazal
    I have been getting an intermittent issue when executing to_number function in the where clause on a varchar2 column if number of records exceed a certain number n. I used n as there is no exact number of records on which it happens. On one DB it happens after n was 1 million on another when it was 0.1. million. E.g. I have a table with 10 million records say Table Country which has field1 varchar2 containing numberic data and Id If I do a query as an example select * from country where to_number(field1) = 23 and id 1 and id < 100000 This works But if i do the query select * from country where to_number(field1) = 23 and id 1 and id < 100001 It fails saying invalid number Next I try the query select * from country where to_number(field1) = 23 and id 2 and id < 100001 It works again As I only got invalid number it was confusing, but in the log file it said Memory Notification: Library Cache Object loaded into SGA Heap size 3823K exceeds notification threshold (2048K) KGL object name :with sqlplan as ( select c006 object_owner, c007 object_type,c008 object_name from htmldb_collections where COLLECTION_NAME='HTMLDB_QUERY_PLAN' and c007 in ('TABLE','INDEX','MATERIALIZED VIEW','INDEX (UNIQUE)')), ws_schemas as( select schema from wwv_flow_company_schemas where security_group_id = :flow_security_group_id), t as( select s.object_owner table_owner,s.object_name table_name, d.OBJECT_ID from sqlplan s,sys.dba_objects d It seems its related to SGA size, but google did not give me much help on this. Does anyone have any idea about this issue with TO_NUMBER or oracle functions for large data?

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  • Detecting changes between rows with same ID

    - by Noah
    I have a table containing some names and their associated ID, along with a snapshot: snapshot, id, name I need to identify when a name has changed for an id between snapshots. For example, in the following data: 1, 0, 'MOUSE_SPEED' 1, 1, 'MOUSE_POS' 1, 2, 'KEYBOARD_STATE' 2, 0, 'MOUSE_BUTTONS' 2, 1, 'MOUSE_POS' 2, 2, 'KEYBOARD_STATE' ...the meaning of id 0 changed with snapshot 2, but the others remained the same. I'd like to construct a query that (ideally) returns: 1, 0, 'MOUSE_SPEED' 2, 0, 'MOUSE_BUTTONS' I am using PostgreSQL v8.4.2.

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  • How to secure phpMyAdmin

    - by Andrei
    Hi, I have noticed that there are strange requests to my website trying to find phpmyadmin, like /phpmyadmin/ /pma/ etc. Now I have installed PMA on Ubuntu via apt and would like to access it via webaddress different from /phpmyadmin/. What can I do to change it? Thanks

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  • Higher speed options for executing very large (20 GB) .sql file in MySQL

    - by Jonogan
    My firm was delivered a 20+ GB .sql file in reponse to a request for data from the gov't. I don't have many options for getting the data in a different format, so I need options for how to import it in a reasonable amount of time. I'm running it on a high end server (Win 2008 64bit, MySQL 5.1) using Navicat's batch execution tool. It's been running for 14 hours and shows no signs of being near completion. Does anyone know of any higher speed options for such a transaction? Or is this what I should expect given the large file size? Thanks

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  • mysql subquery strangely slow

    - by aviv
    I have a query to select from another sub-query select. While the two queries look almost the same the second query (in this sample) runs much slower: SELECT user.id ,user.first_name -- user.* FROM user WHERE user.id IN (SELECT ref_id FROM education WHERE ref_type='user' AND education.institute_id='58' AND education.institute_type='1' ); This query takes 1.2s Explain on this query results: id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY user index first_name 152 141192 Using where; Using index 2 DEPENDENT SUBQUERY education index_subquery ref_type,ref_id,institute_id,institute_type,ref_type_2 ref_id 4 func 1 Using where The second query: SELECT -- user.id -- user.first_name user.* FROM user WHERE user.id IN (SELECT ref_id FROM education WHERE ref_type='user' AND education.institute_id='58' AND education.institute_type='1' ); Takes 45sec to run, with explain: id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY user ALL 141192 Using where 2 DEPENDENT SUBQUERY education index_subquery ref_type,ref_id,institute_id,institute_type,ref_type_2 ref_id 4 func 1 Using where Why is it slower if i query only by index fields? Why both queries scans the full length of the user table? Any ideas how to improve? Thanks.

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  • In SQL server, to convert a varchar which have this format (nnn:nn:nn)

    - by user1688917
    I have this varchar format as time accumulation and i want to convert it to an integer to do a SUM and get the total time for a group. The fist part which may be 1, 2, 3, 4 or even five digits represent the accumulation of Hours and then seperated by a colon. then come the second part which is accumulation of minutes and last accumulation of seconds (2 digits each). How to convert this to integer in one query if possile.

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  • How do I perform 'WHERE' on groups of rows?

    - by Drew
    I have a table, which looks like: +-----------+----------+ + person_id + group_id + +-----------+----------+ + 1 + 10 + + 1 + 20 + + 1 + 30 + + 2 + 10 + + 2 + 20 + + 3 + 10 + +-----------+----------+ I need a query such that only person_ids with groups 10 AND 20 AND 30 are returned (only person_id: 1). I am not sure how to do this, as from what I can see it would require me to group the rows by person_id and then select the rows which contain all group_ids. I'm looking for something which will preserve the use of keys without resorting to string operations on group_concat() or such.

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  • mysql db connection

    - by Dragster
    hi there i have been searching the web for a connection between my android simulator and a mysql db. I've fount that you can't connect directly but via a webserver. The webserver wil handle my request from my android. I fount the following code on www.helloandroid.com But i don't understand. If i run this code on the simulator nothing happens. The screen stays black. Where does Log.i land. In the android screen or in the error log or somewhere else? Can somebody help me with this code? package app.android.ticket; import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader; import java.util.ArrayList; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.client.HttpClient; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import android.app.Activity; import android.os.Bundle; import android.util.Log; public class fetchData extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); //call the method to run the data retreival getServerData(); } public static final String KEY_121 = "http://www.jorisdek.nl/android/getAllPeopleBornAfter.php"; public fetchData() { Log.e("fetchData", "Initialized ServerLink "); } private void getServerData() { InputStream is = null; String result = ""; //the year data to send ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(); nameValuePairs.add(new BasicNameValuePair("year","1980")); //http post try{ HttpClient httpclient = new DefaultHttpClient(); HttpPost httppost = new HttpPost(KEY_121); httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs)); HttpResponse response = httpclient.execute(httppost); HttpEntity entity = response.getEntity(); is = entity.getContent(); }catch(Exception e){ Log.e("log_tag", "Error in http connection "+e.toString()); } //convert response to string try{ BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } is.close(); result=sb.toString(); }catch(Exception e){ Log.e("log_tag", "Error converting result "+e.toString()); } //parse json data try{ JSONArray jArray = new JSONArray(result); for(int i=0;i<jArray.length();i++){ JSONObject json_data = jArray.getJSONObject(i); Log.i("log_tag","id: "+json_data.getInt("id")+ ", name: "+json_data.getString("name")+ ", sex: "+json_data.getInt("sex")+ ", birthyear: "+json_data.getInt("birthyear") ); } }catch(JSONException e){ Log.e("log_tag", "Error parsing data "+e.toString()); } } }

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  • Optimize a MySQL count each duplicate Query

    - by Onema
    I have the following query That gets the city name, city id, the region name, and a count of duplicate names for that record: SELECT Country_CA.City AS currentCity, Country_CA.CityID, globe_region.region_name, ( SELECT count(Country_CA.City) FROM Country_CA WHERE City LIKE currentCity ) as counter FROM Country_CA LEFT JOIN globe_region ON globe_region.region_id = Country_CA.RegionID AND globe_region.country_code = Country_CA.CountryCode ORDER BY City This example is for Canada, and the cities will be displayed on a dropdown list. There are a few towns in Canada, and in other countries, that have the same names. Therefore I want to know if there is more than one town with the same name region name will be appended to the town name. Region names are found in the globe_region table. Country_CA and globe_region look similar to this (I have changed a few things for visualization purposes) CREATE TABLE IF NOT EXISTS `Country_CA` ( `City` varchar(75) NOT NULL DEFAULT '', `RegionID` varchar(10) NOT NULL DEFAULT '', `CountryCode` varchar(10) NOT NULL DEFAULT '', `CityID` int(11) NOT NULL DEFAULT '0', PRIMARY KEY (`City`,`RegionID`), KEY `CityID` (`CityID`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; AND CREATE TABLE IF NOT EXISTS `globe_region` ( `country_code` char(2) COLLATE utf8_unicode_ci NOT NULL, `region_code` char(2) COLLATE utf8_unicode_ci NOT NULL, `region_name` varchar(50) COLLATE utf8_unicode_ci NOT NULL, PRIMARY KEY (`country_code`,`region_code`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci; The query on the top does exactly what I want it to do, but It takes way too long to generate a list for 5000 records. I would like to know if there is a way to optimize the sub-query in order to obtain the same results faster. the results should look like this City CityID region_name counter sheraton 2349269 British Columbia 1 sherbrooke 2349270 Quebec 2 sherbrooke 2349271 Nova Scotia 2 shere 2349273 British Columbia 1 sherridon 2349274 Manitoba 1

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  • Rails, search item in different model?

    - by Danny McClelland
    Hi Everyone, I have a kase model which I am using a simple search form in. The problem I am having is some kases are linked to companies through a company model, and people through a people model. At the moment my search (in Kase model) looks like this: # SEARCH FACILITY def self.search(search) search_condition = "%" + search + "%" find(:all, :conditions => ['jobno LIKE ? OR casesubject LIKE ? OR transport LIKE ? OR goods LIKE ? OR comments LIKE ? OR invoicenumber LIKE ? OR netamount LIKE ? OR clientref LIKE ? OR kase_status LIKE ? OR lyingatlocationaddresscity LIKE ?', search_condition, search_condition, search_condition, search_condition, search_condition, search_condition, search_condition, search_condition, search_condition, search_condition]) end What I am trying to work out, is what condition can I add to allow a search by Company or Person to show the cases they are linked to. @kase.company.companyname and company.companyname don't work :( Is this possible? Thanks, Danny

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  • How do you determine an acceptable response time for App Engine DB requests?

    - by qiq
    According to this discussion of Google App Engine on Hacker News, A DB (read) request takes over 100ms on the datastore. That's insane and unusable for about 90% of applications. How do you determine what is an acceptable response time for a DB read request? I have been using App Engine without noticing any issues with DB responsiveness. But, on the other hand, I'm not sure I would even know what to look for in that regard :)

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  • Syntax for "RETURNING" clause in Mysql PDO

    - by dmontain
    I'm trying to add a record, and at the same time return the id of that record added. I read it's possible to do it with a RETURNING clause. $stmt->prepare("INSERT INTO tablename (field1, field2) VALUES (:value1, :value2) RETURNING id"); but the insertion fails when I add RETURNING. There is an auto-incremented field called id in the table being added to. Can someone see anything wrong with my syntax? or maybe PDO does not support RETURNING?

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  • WPF: How to bind and update display with DataContext

    - by Am
    I'm trying to do the following thing: I have a TabControl with several tabs. Each TabControlItem.Content points to PersonDetails which is a UserControl Each BookDetails has a dependency property called IsEditMode I want a control outside of the TabControl , named ToggleEditButton, to be updated whenever the selected tab changes. I thought I could do this by changing the ToggleEditButton data context, by it doesn't seem to work (but I'm new to WPF so I might way off) The code changing the data context: private void tabControl1_SelectionChanged(object sender, SelectionChangedEventArgs e) { if (e.Source is TabControl) { if (e.Source.Equals(tabControl1)) { if (tabControl1.SelectedItem is CloseableTabItem) { var tabItem = tabControl1.SelectedItem as CloseableTabItem; RibbonBook.DataContext = tabItem.Content as BookDetails; ribbonBar.SelectedTabItem = RibbonBook; } } } } The DependencyProperty under BookDetails: public static readonly DependencyProperty IsEditModeProperty = DependencyProperty.Register("IsEditMode", typeof (bool), typeof (BookDetails), new PropertyMetadata(true)); public bool IsEditMode { get { return (bool)GetValue(IsEditModeProperty); } set { SetValue(IsEditModeProperty, value); SetValue(IsViewModeProperty, !value); } } And the relevant XAML: <odc:RibbonTabItem Title="Book" Name="RibbonBook"> <odc:RibbonGroup Title="Details" Image="img/books2.png" IsDialogLauncherVisible="False"> <odc:RibbonToggleButton Content="Edit" Name="ToggleEditButton" odc:RibbonBar.MinSize="Medium" SmallImage="img/edit_16x16.png" LargeImage="img/edit_32x32.png" Click="Book_EditDetails" IsChecked="{Binding Path=IsEditMode, Mode=TwoWay}"/> ... There are two things I want to accomplish, Having the button reflect the IsEditMode for the visible tab, and have the button change the property value with no code behind (if posible) Any help would be greatly appriciated.

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  • Maximum Row in DBMS

    - by Am1rr3zA
    Is there any limit to maximum row of table in DBMS (specially MySQL)? I want create table for saving logfile and it's row increase so fast I want know what shoud I do to prevent any problem.

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  • How can I check a type's dependents order to drop them and replace/modify the initial type?

    - by pctroll
    I tried to modify a type using the following code and it gave me the error code: 'ORA-02303'. I don't know much about Oracle or PL/SQL but I need to solve this; so I'd appreciate any further help with this. Thanks in advance. The code is just an example. But then again, I need to check its dependents first. create or replace type A as object ( x_ number, y_ varchar2(10), member procedure to_upper ); /

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  • Reading directly from the Doctrine Searchable index table

    - by phidah
    I've got a Doctrine table with the Searchable behavior enabled. Whenever a record is created, an index is made in another table. I have a model called Entry and the behavior automatically created the table entry_index. My question now is: How can I - without using the search(...) methods of my model use the data from this table? I want to create a tag cloud of the words most used, and the data in the index table is exactly what I need.

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  • Migrating from hand-written persistence layer to ORM

    - by Sergey Mikhanov
    Hi community, We are currently evaluating options for migrating from hand-written persistence layer to ORM. We have a bunch of legacy persistent objects (~200), that implement simple interface like this: interface JDBC { public long getId(); public void setId(long id); public void retrieve(); public void setDataSource(DataSource ds); } When retrieve() is called, object populates itself by issuing handwritten SQL queries to the connection provided using the ID it received in the setter (this usually is the only parameter to the query). It manages its statements, result sets, etc itself. Some of the objects have special flavors of retrive() method, like retrieveByName(), in this case a different SQL is issued. Queries could be quite complex, we often join several tables to populate the sets representing relations to other objects, sometimes join queries are issued on-demand in the specific getter (lazy loading). So basically, we have implemented most of the ORM's functionality manually. The reason for that was performance. We have very strong requirements for speed, and back in 2005 (when this code was written) performance tests has shown that none of mainstream ORMs were that fast as hand-written SQL. The problems we are facing now that make us think of ORM are: Most of the paths in this code are well-tested and are stable. However, some rarely-used code is prone to result set and connection leaks that are very hard to detect We are currently squeezing some additional performance by adding caching to our persistence layer and it's a huge pain to maintain the cached objects manually in this setup Support of this code when DB schema changes is a big problem. I am looking for an advice on what could be the best alternative for us. As far as I know, ORMs has advanced in last 5 years, so it might be that now there's one that offers an acceptable performance. As I see this issue, we need to address those points: Find some way to reuse at least some of the written SQL to express mappings Have the possibility to issue native SQL queries without the necessity to manually decompose their results (i.e. avoid manual rs.getInt(42) as they are very sensitive to schema changes) Add a non-intrusive caching layer Keep the performance figures. Is there any ORM framework you could recommend with regards to that?

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  • MySQL: automatic rollback on transaction failure

    - by praksant
    Is there any way to set MySQL to rollback any transaction on first error/warning automatically? Now if everything goes well, it commits, but on failure it leaves transaction open and on another start of transaction it commits incomplete changes from failed transaction. (I'm executing queries from php, but i don't want to check in php for failure, as it would make more calls between mysql server and webserver.) Thank you

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