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  • C#: Fill DataGridView From Anonymous Linq Query

    - by mdvaldosta
    // From my form BindingSource bs = new BindingSource(); private void fillStudentGrid() { bs.DataSource = Admin.GetStudents(); dgViewStudents.DataSource = bs; } // From the Admin class public static List<Student> GetStudents() { DojoDBDataContext conn = new DojoDBDataContext(); var query = (from s in conn.Students select new Student { ID = s.ID, FirstName = s.FirstName, LastName = s.LastName, Belt = s.Belt }).ToList(); return query; } I'm trying to fill a datagridview control in Winforms, and I only want a few of the values. The code compiles, but throws a runtime error: Explicit construction of entity type 'DojoManagement.Student' in query is not allowed. Is there a way to get it working in this manner?

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  • Disable eclipselink caching and query caching - not working?

    - by James
    I am using eclipselink JPA with a database which is also being updated externally to my application. For that reason there are tables I want to query every few seconds. I can't get this to work even when I try to disable the cache and query cache. For example: EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("default"); EntityManager em = entityManagerFactory.createEntityManager(); MyLocation one = em.createNamedQuery("MyLocation.findMyLoc").getResultList().get(0); Thread.sleep(10000); MyLocation two = em.createNamedQuery("MyLocation.findMyLoc").getResultList().get(0); System.out.println(one.getCapacity() + " - " + two.getCapacity()); Even though the capacity changes while my application is sleeping the println always prints the same value for one and two. I have added the following to the persistence.xml <property name="eclipselink.cache.shared.default" value="false"/> <property name="eclipselink.query-results-cache" value="false"/> I must be missing something but am running out of ideas. James

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  • JPQL cross tab query

    - by Phil
    Hi can anyone tell me if its possible to write a cross tab query in JPQL? (I'm using eclipse link JPA2) An example of a cross tab query in SQL can found here http://onlamp.com/pub/a/onlamp/2003/12/04/crosstabs.html SELECT dept, COUNT(CASE WHEN gender = 'm' THEN id ELSE NULL END) AS m, COUNT(CASE WHEN gender = 'f' THEN id ELSE NULL END) AS f, COUNT(*) AS total FROM person GROUP BY dept How can I do the same thing as a single query in JPQL? Looking at the spec it doesn't seem to look like CASE is valid in COUNT Is there any other way?

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  • WM_CONCAT with DISTINCT Clause - Compiled Package versus Stand-Alone Query Issue

    - by Reimius
    I was writing some program that uses the WM_CONCAT function. When I run this query: SELECT WM_CONCAT(DISTINCT employee_id) FROM employee WHERE ROWNUM < 20; It works fine. When I try to compile the relatively same query in a package function or procedure, it produces this error: PL/SQL: ORA-30482: DISTINCT option not allowed for this function FUNCTION fetch_raw_data_by_range RETURN VARCHAR2 IS v_some_string VARCHAR2(32000); BEGIN SELECT WM_CONCAT(DISTINCT employee_id) INTO v_some_string FROM employee WHERE ROWNUM < 20; RETURN v_some_string; END; I realize WM_CONCAT is not officially supported, but can someone explain why it would work as a stand alone query with DISTINCT, but not compile in a package?

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  • Fill WinForms DataGridView From Anonymous Linq Query

    - by mdvaldosta
    // From my form BindingSource bs = new BindingSource(); private void fillStudentGrid() { bs.DataSource = Admin.GetStudents(); dgViewStudents.DataSource = bs; } // From the Admin class public static List<Student> GetStudents() { DojoDBDataContext conn = new DojoDBDataContext(); var query = (from s in conn.Students select new Student { ID = s.ID, FirstName = s.FirstName, LastName = s.LastName, Belt = s.Belt }).ToList(); return query; } I'm trying to fill a datagridview control in Winforms, and I only want a few of the values. The code compiles, but throws a runtime error: Explicit construction of entity type 'DojoManagement.Student' in query is not allowed. Is there a way to get it working in this manner?

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  • Mysql Sub Select Query Optimization

    - by Matt
    I'm running a query daily to compile stats - but it seems really inefficient. This is the Query: SELECT a.id, tstamp, label_id, (SELECT author_id FROM b WHERE b.tid = a.id ORDER BY b.tstamp DESC LIMIT 1) AS author_id FROM a, b WHERE (status = '2' OR status = '3') AND category != 6 AND a.id = b.tid AND (b.type = 'C' OR b.type = 'R') AND a.tstamp1 BETWEEN {$timestamp_start} AND {$timestamp_end} ORDER BY b.tstamp DESC LIMIT 500 This query seems to run really slow. Apologies for the crap naming - I've been asked to not reveal the actual table names. The reason there is a sub select is because the outer select gets one row from the table a and it gets a row from table b. But also need to know the latest author_id from table b as well, so I run a subselect to return that one. I don't want to run another select inside a php loop - as that is also inefficient. It works correctly - I just need to find a much faster way of getting this data set.

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  • using a php variable in the WHERE clause of a mysql query

    - by user1262890
    I'm running a very simple query that I think should work. The only thing that I haven't done before is put a php variable in the WHERE clause of the query. The variable $X is a numerical value, say 100. When I run this query, I just get a value of 0 returned. Am I doing something obviously stupid? SELECT generator_64k.n FROM generator_64k WHERE generator_64k.n<= '$X' I've looked around the web and also tried this: SELECT generator_64k.n FROM generator_64k WHERE generator_64k.n<= '" . $X . "' But this also just returns 0. Any ideas? Thanks in advance.

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  • Query optimization

    - by Lijo
    Hi Team, I am trying to learn SQL query optimization using SQL Server 2005. However, I did not find any practical example where I can improve performance by tweaking query alone. Can you please list some example queries - prior and after optimization? It has to be query tuning – not adding index, not making covering index, not making any alteration to table. No change is supposed to be done on table and index. [ I understand that indexes are important. This is only for learning purpose] It would be great if you can exaplain using temp table instead of refering any sample databases like adventureworks. Expecting your support... Thanks Lijo

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  • JPA + Hibernate + Named Query + how to JOIN a subquery result

    - by Srihari
    Can anybody help me in converting the following native query into a Named Query? Native Query: SELECT usr1.user_id, urr1.role_id, usr2.user_id, urr2.role_id, usr1.school_id, term.term_name, count(material.material_id) as "Total Book Count", fpc.FOLLETT_PENDING_COUNT as "Follett Pending Count", rrc.RESOLUTION_REQUIRED_COUNT as "Resolution Required Count" FROM va_school sch JOIN va_user_school_rel usr1 on sch.school_id=usr1.school_id JOIN va_user_role_rel urr1 on usr1.user_id=urr1.user_id and urr1.role_id=1001 JOIN va_user_school_rel usr2 on sch.school_id=usr2.school_id JOIN va_user_role_rel urr2 on usr2.user_id=urr2.user_id and urr2.role_id=1002 JOIN va_term term on term.school_id = usr1.school_id JOIN va_class course on course.term_id = term.term_id JOIN va_material material on material.class_id = course.class_id LEFT JOIN (SELECT VA_CLASS.TERM_ID as "TERM_ID", COUNT(*) as "FOLLETT_PENDING_COUNT" FROM VA_CLASS JOIN VA_MATERIAL ON VA_MATERIAL.CLASS_ID = VA_CLASS.CLASS_ID WHERE VA_CLASS.reference_flag = 'A' AND trunc(VA_MATERIAL.FOLLETT_STATUS) = 0 GROUP BY VA_CLASS.TERM_ID) fpc on term.term_id = fpc.term_id LEFT JOIN (SELECT VA_CLASS.TERM_ID as "TERM_ID", COUNT(*) as "RESOLUTION_REQUIRED_COUNT" FROM VA_CLASS JOIN VA_MATERIAL ON VA_MATERIAL.CLASS_ID = VA_CLASS.CLASS_ID WHERE VA_CLASS.reference_flag = 'A' AND trunc(VA_MATERIAL.FOLLETT_STATUS) = 1 GROUP BY VA_CLASS.TERM_ID) rrc on term.term_id = rrc.term_id WHERE course.reference_flag = 'A' GROUP BY usr1.user_id, urr1.role_id, usr2.user_id, urr2.role_id, usr1.school_id, term.term_name, fpc.FOLLETT_PENDING_COUNT, rrc.RESOLUTION_REQUIRED_COUNT ORDER BY usr1.school_id, term.term_name; Thanks in advance. Srihari

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  • JPA + Hibernate + Named Query + how to JOIN a subquery result

    - by Srihari
    Hi, Can anybody help me in converting the following native query into a Named Query? Native Query: SELECT usr1.user_id, urr1.role_id, usr2.user_id, urr2.role_id, usr1.school_id, term.term_name, count(material.material_id) as "Total Book Count", fpc.FOLLETT_PENDING_COUNT as "Follett Pending Count", rrc.RESOLUTION_REQUIRED_COUNT as "Resolution Required Count" FROM va_school sch JOIN va_user_school_rel usr1 on sch.school_id=usr1.school_id JOIN va_user_role_rel urr1 on usr1.user_id=urr1.user_id and urr1.role_id=1001 JOIN va_user_school_rel usr2 on sch.school_id=usr2.school_id JOIN va_user_role_rel urr2 on usr2.user_id=urr2.user_id and urr2.role_id=1002 JOIN va_term term on term.school_id = usr1.school_id JOIN va_class course on course.term_id = term.term_id JOIN va_material material on material.class_id = course.class_id LEFT JOIN (SELECT VA_CLASS.TERM_ID as "TERM_ID", COUNT(*) as "FOLLETT_PENDING_COUNT" FROM VA_CLASS JOIN VA_MATERIAL ON VA_MATERIAL.CLASS_ID = VA_CLASS.CLASS_ID WHERE VA_CLASS.reference_flag = 'A' AND trunc(VA_MATERIAL.FOLLETT_STATUS) = 0 GROUP BY VA_CLASS.TERM_ID) fpc on term.term_id = fpc.term_id LEFT JOIN (SELECT VA_CLASS.TERM_ID as "TERM_ID", COUNT(*) as "RESOLUTION_REQUIRED_COUNT" FROM VA_CLASS JOIN VA_MATERIAL ON VA_MATERIAL.CLASS_ID = VA_CLASS.CLASS_ID WHERE VA_CLASS.reference_flag = 'A' AND trunc(VA_MATERIAL.FOLLETT_STATUS) = 1 GROUP BY VA_CLASS.TERM_ID) rrc on term.term_id = rrc.term_id WHERE course.reference_flag = 'A' GROUP BY usr1.user_id, urr1.role_id, usr2.user_id, urr2.role_id, usr1.school_id, term.term_name, fpc.FOLLETT_PENDING_COUNT, rrc.RESOLUTION_REQUIRED_COUNT ORDER BY usr1.school_id, term.term_name; Thanks in advance. Srihari

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  • Nhibernate many to many criteria query with subselect

    - by Max
    I have a simple example of a blog: a Post table, a Tag table and a Post_Tag_MM lookup table linking the two tables. I use this hql query in order to fetch all posts, that DONT have some tags: var result = session .CreateQuery(@" select p from Post p join p.Tags t where (select count(ti) from p.Tags ti where ti.Uid in (:uidList)) = 0 ") .SetParameterList("uidList", uidList) .SetResultTransformer(new DistinctRootEntityResultTransformer()) .List<Post>(); How can this many-to-many query and the subselect translated into a criteria query? I dont quite understand the DetachedCriteria API yet and could not get it to return the right resultset. Thank you very much in advance. Regards, Max

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  • Optimizing Oracle query

    - by Omnipresent
    SELECT MAX(verification_id) FROM VERIFICATION_TABLE WHERE head = 687422 AND mbr = 23102 AND RTRIM(LTRIM(lname)) = '.iq bzw' AND TO_CHAR(dob,'MM/DD/YYYY')= '08/10/2004' AND system_code = 'M'; This query is taking 153 seconds to run. there are millions of rows in VERIFICATION_TABLE. I think query is taking long because of the functions in where clause. However, I need to do ltrim rtrim on the columns and also date has to be matched in MM/DD/YYYY format. How can I optimize this query?

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  • App engine datastore - query on Enum fields.

    - by Gopi
    I am using GAE(Java) with JDO for persistence. I have an entity with a Enum field which is marked as @Persistent and gets saved correctly into the datastore (As observed from the Datastore viewer in Development Console). But when I query these entities putting a filter based on the Enum value, it is always returning me all the entities whatever value I specify for the enum field. I know GAE java supports enums being persisted just like basic datatypes. But does it also allow retrieving/querying based on them? Google search could not point me to any such example code. Details: I have printed the Query just before being executed. So in two cases the query looks like - SELECT FROM com.xxx.yyy.User WHERE role == super ORDER BY key desc RANGE 0,50 SELECT FROM com.xxx.yyy.User WHERE role == admin ORDER BY key desc RANGE 0,50 Both above queries return me all the User entities from datastore in spite of datastore viewer showing some Users are of type 'admin' and some are of type 'super'.

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  • Query Not Working

    - by John
    Hello, The simple query below is not working. Any idea why? When I echo the three variables, the correct values are returned, so I know I have variables. Thanks in advance, John $comment = $_POST['comment']; $uid = $_POST['uid']; $subid = $_POST['submissionid']; echo $comment; echo $uid; echo $subid; mysql_connect("mysqlv12", "username", "password") or die(mysql_error()); mysql_select_db("database") or die(mysql_error()); $query = sprintf("INSERT INTO comment VALUES (NULL, '%s', '%s', '%s', NULL, NULL)", $uid, $subid, $comment); mysql_query($query);

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  • Opencart Dashboard show last months statistics

    - by John Magnolia
    How could I added the option to show the statistics for last month. PHP public function chart() { $this->load->language('common/home'); $data = array(); $data['order'] = array(); $data['customer'] = array(); $data['xaxis'] = array(); $data['order']['label'] = $this->language->get('text_order'); $data['customer']['label'] = $this->language->get('text_customer'); if (isset($this->request->get['range'])) { $range = $this->request->get['range']; } else { $range = 'month'; } switch ($range) { case 'day': for ($i = 0; $i < 24; $i++) { $query = $this->db->query("SELECT COUNT(*) AS total FROM `" . DB_PREFIX . "order` WHERE order_status_id > '0' AND (DATE(date_added) = DATE(NOW()) AND HOUR(date_added) = '" . (int)$i . "') GROUP BY HOUR(date_added) ORDER BY date_added ASC"); if ($query->num_rows) { $data['order']['data'][] = array($i, (int)$query->row['total']); } else { $data['order']['data'][] = array($i, 0); } $query = $this->db->query("SELECT COUNT(*) AS total FROM " . DB_PREFIX . "customer WHERE DATE(date_added) = DATE(NOW()) AND HOUR(date_added) = '" . (int)$i . "' GROUP BY HOUR(date_added) ORDER BY date_added ASC"); if ($query->num_rows) { $data['customer']['data'][] = array($i, (int)$query->row['total']); } else { $data['customer']['data'][] = array($i, 0); } $data['xaxis'][] = array($i, date('H', mktime($i, 0, 0, date('n'), date('j'), date('Y')))); } break; case 'week': $date_start = strtotime('-' . date('w') . ' days'); for ($i = 0; $i < 7; $i++) { $date = date('Y-m-d', $date_start + ($i * 86400)); $query = $this->db->query("SELECT COUNT(*) AS total FROM `" . DB_PREFIX . "order` WHERE order_status_id > '0' AND DATE(date_added) = '" . $this->db->escape($date) . "' GROUP BY DATE(date_added)"); if ($query->num_rows) { $data['order']['data'][] = array($i, (int)$query->row['total']); } else { $data['order']['data'][] = array($i, 0); } $query = $this->db->query("SELECT COUNT(*) AS total FROM `" . DB_PREFIX . "customer` WHERE DATE(date_added) = '" . $this->db->escape($date) . "' GROUP BY DATE(date_added)"); if ($query->num_rows) { $data['customer']['data'][] = array($i, (int)$query->row['total']); } else { $data['customer']['data'][] = array($i, 0); } $data['xaxis'][] = array($i, date('D', strtotime($date))); } break; default: case 'month': for ($i = 1; $i <= date('t'); $i++) { $date = date('Y') . '-' . date('m') . '-' . $i; $query = $this->db->query("SELECT COUNT(*) AS total FROM `" . DB_PREFIX . "order` WHERE order_status_id > '0' AND (DATE(date_added) = '" . $this->db->escape($date) . "') GROUP BY DAY(date_added)"); if ($query->num_rows) { $data['order']['data'][] = array($i, (int)$query->row['total']); } else { $data['order']['data'][] = array($i, 0); } $query = $this->db->query("SELECT COUNT(*) AS total FROM " . DB_PREFIX . "customer WHERE DATE(date_added) = '" . $this->db->escape($date) . "' GROUP BY DAY(date_added)"); if ($query->num_rows) { $data['customer']['data'][] = array($i, (int)$query->row['total']); } else { $data['customer']['data'][] = array($i, 0); } $data['xaxis'][] = array($i, date('j', strtotime($date))); } break; case 'year': for ($i = 1; $i <= 12; $i++) { $query = $this->db->query("SELECT COUNT(*) AS total FROM `" . DB_PREFIX . "order` WHERE order_status_id > '0' AND YEAR(date_added) = '" . date('Y') . "' AND MONTH(date_added) = '" . $i . "' GROUP BY MONTH(date_added)"); if ($query->num_rows) { $data['order']['data'][] = array($i, (int)$query->row['total']); } else { $data['order']['data'][] = array($i, 0); } $query = $this->db->query("SELECT COUNT(*) AS total FROM " . DB_PREFIX . "customer WHERE YEAR(date_added) = '" . date('Y') . "' AND MONTH(date_added) = '" . $i . "' GROUP BY MONTH(date_added)"); if ($query->num_rows) { $data['customer']['data'][] = array($i, (int)$query->row['total']); } else { $data['customer']['data'][] = array($i, 0); } $data['xaxis'][] = array($i, date('M', mktime(0, 0, 0, $i, 1, date('Y')))); } break; } $this->response->setOutput(json_encode($data)); } HTML <select name="range"> <option value="day">Today</option> <option value="week">This Week</option> <option value="month">This Month</option> <option value="year">This Year</option> </select>

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  • Set query FROM table using report parameter in BIRT

    - by Adam
    Hi, I am using the BIRT report writer, and I have multiple tables with the same data structure. In my report design, I want to select the table my query uses as a report parameter (as part of a mysql query in the data set) -- but I can't figure it out. When I create the data set, it's great that I can use parameters in the form of SELECT * FROM WHERE ?, and set these to report parameters, but I get an error if I set the ? to the table, such as: SELECT * FROM ? WHERE 1 Is there another way I can do this? As it's java, I assume the syntax follows that of a PreparedStatement. In BIRT 2.5 there is a property binding option under the data set dialog... and I've tried setting my query as: "SELECT * FROM "+params["DataTable"].value+" WHERE 1", but that was also results in an error.

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  • How to dynamically choose two fields from a Linq query as a result

    - by Dr. Zim
    If you have a simple Linq query like: var result = from record in db.Customer select new { Text = record.Name, Value = record.ID.ToString() }; which is returning an object that can be mapped to a Drop Down List, is it possible to dynamically specify which fields map to Text and Value? Of course, you could do a big case (switch) statement, then code each Linq query separately but this isn't very elegant. What would be nice would be something like: (pseudo code) var myTextField = db.Customer["Name"]; // Could be an enumeration?? var myValueField = db.Customer["ID"]; // Idea: choose the field outside the query var result = from record in db.Customer select new { Text = myTextField, Value = myValueField };

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  • Optimising SQL distance query

    - by Alex
    I'm running an MySQL query that returns results based on location. However I have noticed recently that its really slowing down my PHP app. I used CodeIgniter and the profiler shows the query taking 4.2seconds. The geoname table has 500,000 rows. I have some indexes on the key columns, how else can speed up this query? Here is my SQL: SELECT `products`.`product_name`, `geoname`.`geonameid`, `geoname`.`latitude`, `geoname`.`longitude`, `products`.`product_id`, AVG(ratings.vote) as rating, count(comments.comment_id) as total_comments, (6371 * acos(cos(radians(38.7666667)) * cos(radians(geoname.latitude)) * cos(radians(geoname.longitude) - radians(-3.3833333)) + sin(radians(38.7666667)) * sin(radians(geoname.latitude)))) AS distance FROM (`foods`) JOIN `geoname` ON `geoname`.`geonameid` = `products`.`geoname_id` LEFT JOIN `ratings` ON `ratings`.`var_id` = `products`.`product_id` LEFT JOIN `comments` ON `comments`.`var_id` = `products `.`product_id` WHERE `products`.`product_id` != 82 GROUP BY `products`.`product_id` HAVING `distance` < 99 ORDER BY `distance` LIMIT 10

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  • Django query: Count and Group BY

    - by Tyler Lane
    I have a query that I'm trying to figure the "django" way of doing it: I want to take the last 100 calls from Call. Which is easy: calls = Call.objects.all().order_by('-call_time')[:100] However the next part I can't find the way to do it via django's ORM. I want to get a list of the call_types and the number of calls each one has WITHIN that previous queryset i just did. Normally i would do a query like this: "SELECT COUNT(id),calltype FROM call WHERE id IN ( SELECT id FROM call ORDER BY call_time DESC LIMIT 100 ) GROUP BY calltype;" I can't seem to find the django way of doing this particular query. Here are my 2 models: class Call( models.Model ): call_time = models.DateTimeField( "Call Time", auto_now = False, auto_now_add = False ) description = models.CharField( max_length = 150 ) response = models.CharField( max_length = 50 ) event_num = models.CharField( max_length = 20 ) report_num = models.CharField( max_length = 20 ) address = models.CharField( max_length = 150 ) zip_code = models.CharField( max_length = 10 ) geom = models.PointField(srid=4326) calltype = models.ForeignKey(CallType) objects = models.GeoManager() class CallType( models.Model ): name = models.CharField( max_length = 50 ) description = models.CharField( max_length = 150 ) active = models.BooleanField() time_init = models.DateTimeField( "Date Added", auto_now = False, auto_now_add = True ) objects = models.Manager()

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  • Sqlalchemy+elixir: How query with a ManyToMany relationship?

    - by Hugo
    Hi, I'm using sqlalchemy with Elixir and have some troubles trying to make a query.. I have 2 entities, Customer and CustomerList, with a many to many relationship. customer_lists_customers_table = Table('customer_lists_customers', metadata, Column('id', Integer, primary_key=True), Column('customer_list_id', Integer, ForeignKey("customer_lists.id")), Column('customer_id', Integer, ForeignKey("customers.id"))) class Customer(Entity): [...] customer_lists = ManyToMany('CustomerList', table=customer_lists_customers_table) class CustomerList(Entity): [...] customers = ManyToMany('Customer', table=customer_lists_customers_table) I'm tryng to find CustomerList with some customer: customer = [...] CustomerList.query.filter_by(customers.contains(customer)).all() But I get the error: NameError: global name 'customers' is not defined customers seems to be unrelated to the entity fields, there's an special query form to work with relationships (or ManyToMany relationships)? Thanks

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  • .NET: Preserving some, but not all query params during redirect

    - by kasper pedersen
    Hi all, Could someone tell me if the code below would achieve what I want, which is: Check if the query parameters 'return_path' and/or 'user_state' are present in the query string, and if so append them to the query string of the redirect URI. As I'm not a .NET dev and don't have a server to test this on, I was hoping someone could give me some feedback. ArrayList vars = new ArrayList(); vars.Add("return_path"); vars.Add("user_state"); string newUrl = "/new/request/uri" + "?"; ArrayList params = new ArrayList(); foreach ( string key in Request.QueryString ) { if (vars.contains(key)) { params.Add(key + "=" + HttpUtility.URLPathEncode(Request.QueryString[key])); } } String[] paramArr = (String[]) params.ToArray( typeof (string) ); String queryString = String.join("&", paramArr); Response.Redirect(newUrl); Thank you :)

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  • mysql query performance help

    - by Stefano
    Hi I have a quite large table storing words contained in email messages mysql> explain t_message_words; +----------------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------+---------+------+-----+---------+----------------+ | mwr_key | int(11) | NO | PRI | NULL | auto_increment | | mwr_message_id | int(11) | NO | MUL | NULL | | | mwr_word_id | int(11) | NO | MUL | NULL | | | mwr_count | int(11) | NO | | 0 | | +----------------+---------+------+-----+---------+----------------+ table contains about 100M rows mwr_message_id is a FK to messages table mwr_word_id is a FK to words table mwr_count is the number of occurrencies of word mwr_word_id in message mwr_message_id To calculate most used words, I use the following query SELECT SUM(mwr_count) AS word_count, mwr_word_id FROM t_message_words GROUP BY mwr_word_id ORDER BY word_count DESC LIMIT 100; that runs almost forever (more than half an hour on the test server) mysql> show processlist; +----+------+----------------+--------+---------+------+----------------------+----------------------------------------------------- | Id | User | Host | db | Command | Time | State | Info +----+------+----------------+--------+---------+------+----------------------+----------------------------------------------------- processlist | 41 | root | localhost:3148 | tst_db | Query | 1955 | Copying to tmp table | SELECT SUM(mwr_count) AS word_count, mwr_word_id FROM t_message_words GROUP BY mwr_word_id | +----+------+----------------+--------+---------+------+----------------------+----------------------------------------------------- 3 rows in set (0.00 sec) Is there anything I can do to "speed up" the query (apart from adding more ram, more cpu, faster disks)? thank you in advance stefano

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  • SQL Query syntax, I want to use INNER JOIN

    - by amol kadam
    Hi . I'm working on a windows application project using front end "vb.net" & back end "Ms Access" I have problem in wrinting sql query Actually there are 5 tables Transaction,items,itemtitle,itemtype & userinfo. check the following query & with this referance if u get idea then plz change in correct query Thanking You SELECT TRANSACTIONS.ACCESSIONNO AS ACCESSIONNO,TRANSACTIONS.TYPEID, TRANSACTIONS.CHECKOUTDATE AS CHECKOUTDATE,ITEMTITLE.ITEMTITLE, TRANSACTIONS.CHECKEDOUTBY, USERINFO.FULLNAME_ENG, USERINFO.FULLNAME_MAR, TRANSACTIONS.ACCOUNTNO, ITEMTYPE.TYPES_MAR, ITEMTYPE.TYPES_ENG FROM TRANSACTIONS,ITEMTYPE, ITEMTITLE, USERINFO WHERE TRANSACTIONS.ACCOUNTNO=USERINFO.ACCOUNTNO AND TRANSACTIONS.ACCESSIONNO=ITEMS.ACCESSIONNO AND ITEMS.ITEMTITLEID=ITEMTITLE.ITEMTITLEID AND TRANSACTIONS.TYPEID=ITEMTYPE.TYPEID AND TRANSACTIONS.STATUS='Enabled'

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  • Connection Timeout exception for a query using ADO.Net

    - by dragon
    Update: Looks like the query does not throw any timeout. The connection is timing out. This is a sample code for executing a query. Sometimes, while executing time consuming queries, it throws a timeout exception. I cannot use any of these techniques: 1) Increase timeout. 2) Run it asynchronously with a callback. This needs to run in a synchronous manner. please suggest any other techinques to keep the connection alive while executing a time consuming query? private static void CreateCommand(string queryString, string connectionString) { using (SqlConnection connection = new SqlConnection( connectionString)) { SqlCommand command = new SqlCommand(queryString, connection); command.Connection.Open(); command.ExecuteNonQuery(); } }

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