Search Results

Search found 18661 results on 747 pages for 'linq to mysql'.

Page 138/747 | < Previous Page | 134 135 136 137 138 139 140 141 142 143 144 145  | Next Page >

  • LinqToSQL: Not possible to update PrimaryKey?

    - by Zuhaib
    I have a simple table (lets call it Table1) that has a NVARCHAR field as the PK. Table1 has no association with any other tables. When I update Table1's PK column using LinqToSQL it fails. If I update other column it succeeds. I could delete this row and insert new one in Table1, but I don't want to. There is a transaction table which has Table1's PK column as a column. When the PK of Table1 is changed I want no effect in the transaction table. But when the row from Table1 is deleted, I want the transaction rows to be deleted. The cascading is done via Trigger. As there is not association between these two tables, if I update the PK column of Table1 using normal SQL, it works and there is no effect on the transaction table as expected. When I delete the row the trigger deletes the rows from transaction table. For this reason I can't delete and then add new row in Table1. So what can be done to successfully update the PrimaryKey of the Table1?

    Read the article

  • how to call include

    - by user276640
    i have 3 tables with such relationship table1-table2-table3 in code i call include("table2"). but how can i call include table3 so i can access to properties of objects table3? if i call include("table3") it show error A specified Include path is not valid

    Read the article

  • Trappings MySQL Warnings on Calls Wrapped in Classes -- Python

    - by chernevik
    I can't get Python's try/else blocks to catch MySQL warnings when the execution statements are wrapped in classes. I have a class that has as a MySQL connection object as an attribute, a MySQL cursor object as another, and a method that run queries through that cursor object. The cursor is itself wrapped in a class. These seem to run queries properly, but the MySQL warnings they generate are not caught as exceptions in a try/else block. Why don't the try/else blocks catch the warnings? How would I revise the classes or method calls to catch the warnings? Also, I've looked through the prominent sources and can't find a discussion that helps me understand this. I'd appreciate any reference that explains this. Please see code below. Apologies for verbosity, I'm newbie. #!/usr/bin/python import MySQLdb import sys import copy sys.path.append('../../config') import credentials as c # local module with dbase connection credentials #============================================================================= # CLASSES #------------------------------------------------------------------------ class dbMySQL_Connection: def __init__(self, db_server, db_user, db_passwd): self.conn = MySQLdb.connect(db_server, db_user, db_passwd) def getCursor(self, dict_flag=True): self.dbMySQL_Cursor = dbMySQL_Cursor(self.conn, dict_flag) return self.dbMySQL_Cursor def runQuery(self, qryStr, dict_flag=True): qry_res = runQueryNoCursor(qryStr=qryStr, \ conn=self, \ dict_flag=dict_flag) return qry_res #------------------------------------------------------------------------ class dbMySQL_Cursor: def __init__(self, conn, dict_flag=True): if dict_flag: dbMySQL_Cursor = conn.cursor(MySQLdb.cursors.DictCursor) else: dbMySQL_Cursor = conn.cursor() self.dbMySQL_Cursor = dbMySQL_Cursor def closeCursor(self): self.dbMySQL_Cursor.close() #============================================================================= # QUERY FUNCTIONS #------------------------------------------------------------------------------ def runQueryNoCursor(qryStr, conn, dict_flag=True): dbMySQL_Cursor = conn.getCursor(dict_flag) qry_res =runQueryFnc(qryStr, dbMySQL_Cursor.dbMySQL_Cursor) dbMySQL_Cursor.closeCursor() return qry_res #------------------------------------------------------------------------------ def runQueryFnc(qryStr, dbMySQL_Cursor): qry_res = {} qry_res['rows'] = dbMySQL_Cursor.execute(qryStr) qry_res['result'] = copy.deepcopy(dbMySQL_Cursor.fetchall()) qry_res['messages'] = copy.deepcopy(dbMySQL_Cursor.messages) qry_res['query_str'] = qryStr return qry_res #============================================================================= # USAGES qry = 'DROP DATABASE IF EXISTS database_of_armaments' dbConn = dbMySQL_Connection(**c.creds) def dbConnRunQuery(): # Does not trap an exception; warning displayed to standard error. try: dbConn.runQuery(qry) except: print "dbConn.runQuery() caught an exception." def dbConnCursorExecute(): # Does not trap an exception; warning displayed to standard error. dbConn.getCursor() # try/except block does catches error without this try: dbConn.dbMySQL_Cursor.dbMySQL_Cursor.execute(qry) except Exception, e: print "dbConn.dbMySQL_Cursor.execute() caught an exception." print repr(e) def funcRunQueryNoCursor(): # Does not trap an exception; no warning displayed try: res = runQueryNoCursor(qry, dbConn) print 'Try worked. %s' % res except Exception, e: print "funcRunQueryNoCursor() caught an exception." print repr(e) #============================================================================= if __name__ == '__main__': print '\n' print 'EXAMPLE -- dbConnRunQuery()' dbConnRunQuery() print '\n' print 'EXAMPLE -- dbConnCursorExecute()' dbConnCursorExecute() print '\n' print 'EXAMPLE -- funcRunQueryNoCursor()' funcRunQueryNoCursor() print '\n'

    Read the article

  • How can I improve the performance of LinqToSql queries that use EntitySet properties?

    - by DanM
    I'm using LinqToSql to query a small, simple SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of what makes LinqToSql so appealing. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance besides resorting to doing all the joins manually? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view. Update Here are the table definitions for the example I used in my question: create table Order ( Id int identity(1, 1) primary key, ProductName ntext null ) create table Customer ( Id int identity(1, 1) primary key, OrderId int null references Order (Id) )

    Read the article

  • Development Environment for Testing MySQL Replication

    - by Dave Morris
    Is there an easy way to setup an environment on one machine (or a VM) with MySQL replication? I would like to put together a proof of concept of MySQL replication with one Master write instance and two slave instances for reads. I can see doing it across 2 or 3 VMs running on my computer, but that would really bog down my system. I'd rather have everything running on the same VM. What's the best way to proof out scalability solutions like this in a local dev environment? Thanks for your help, Dave

    Read the article

  • Creating SVG map from geometry stored in MySQL

    - by Barnabe
    I have a group of geometries stored in MySQl (as polygon and as well-known text) representing counties. I can build a table of geometries and color codes after querying some county data (say GDP per capita). What is the best way to export this as an SVG map? I cannot find any reference to SVG conversion in the MySQL documentation.

    Read the article

  • How to create view model without sorting collections in memory.

    - by Chevex
    I have a view model (below). public class TopicsViewModel { public Topic Topic { get; set; } public Reply LastReply { get; set; } } I want to populate an IQueryable<TopicsViewModel> with values from my IQueryable<Topic> collection and IQueryable<Reply> collection. I do not want to use the attached entity collection (i.e. Topic.Replies) because I only want the last reply for that topic and doing Topic.Replies.Last() loads the entire entity collection in memory and then grabs the last one in the list. I am trying to stay in IQueryable so that the query is executed in the database. I also don't want to foreach through topics and query replyRepository.Replies because looping through IQueryable<Topic> will start the lazy loading. I'd prefer to build one expression and have all the leg work done in the lower layers. I have the following: IQueryable<TopicsViewModel> topicsViewModel = from x in topicRepository.Topics from y in replyRepository.Replies where y.TopicID == x.TopicID orderby y.PostedDate ascending select new TopicsViewModel { Topic = x, LastReply = y }; But this isn't working. Any ideas how I can populate an IQueryable or IEnumerable of TopicsViewModel so that it queries the database and grabs topics and that topic's last reply? I am trying really hard to avoid grabbing all replies related to that topic. I only want to grab the last reply. Thank you for any insight you have to offer.

    Read the article

  • Mysql Removal of primary key

    - by marionmaiden
    Hello, I've removed the primary key of one table of my MySQL database, but now, when I use the MySQL Administrator and try to edit the data of this table, it doesn't allow me to do this. The button edit that appears in the bottom of the table keeps visible, but unable to click.

    Read the article

  • Error message on using LinqDataSource in webforms

    - by naveen
    Coding Platform: ASP.NET 4.0 I am binding a GridView with LinqDataSource with AutoDelete functionality enabled. GridView is bound to the Products Table. I have a Products Table and a Category Table with an association on CategoryID. If I try to delete a Category that is referred in the Products Table I cannot do that. Its is totally acceptable, but I want the end user to be notified with some error message. Where to catch this error message?

    Read the article

  • Using Time datatype in MySQL without seconds

    - by Alex
    I'm trying to store a 12/24hr (ie; 00:00) clock time in a MySQL database. At the moment I am using the time datatype. This works ok but it insists on adding the seconds to the column. So you enter 09:20 and it is stored as 09:20:00. Is there any way I can limit it in MySQL to just 00:00?

    Read the article

  • which is better, creating a materialized view or a new table?

    - by Carson
    I have some demanding mysql queries that are needed to grap same up-to-date datasets from 5-7 mysql tables. I am thinking of creating a table or materialized view to gather all demanding columns from other tables, so as to increase performance. If I create that table, I may need to do extra insert / update / delete operation each time other tables updated. if I create materialized view, I am worrying if the performance can be greatly improved. Because data from other tables are changing very frequently. Most likely, the view may need to be created first everytime before selecting it. Any ideas? e.g. how to cache? other extra measures I can do?

    Read the article

  • wanna store Object in MySQL database

    - by kandarp
    I have a variable in java which return type is Object(java.lang.Object). I want to store this variable value in MySQL database without casting in any other primitive data type. Is there any data type available in MySQL related to Object? If anybody knows, please reply at your earliest time. Thanks,

    Read the article

  • MySQL 5.1 - logging CREATE/ALTER statements

    - by pako
    Is it possible to log CREATE / ALTER statements issued on a MySQL server? I heard that it could be done with a trigger, but I can't seem to find suitable code anywhere. I would like to log these statements to a table, preferably with the timestamp of when they were issued. Can someone provide me with a sample trigger that would enable me to accomplish this? I would like to log these statements so I can easily synchronize the changes with another MySQL server.

    Read the article

  • PHP - error when insert date into MySQL

    - by Michael Mao
    Hello everyone: I've got a typical problem when trying to insert a date into MySQL. The column defined in MySQL is of type DATE. My PHP version is 5.3.0 Apart from this date-related issue, the rest of my code works just fine. And this is my PHP script to do this: $tablename = BOOKS_TABLE; $insert = mysql_query("INSERT INTO $tablename (barcode, book_name, volume_num,". " author, publisher, item_type, buy_price, buy_date) VALUES ". "(". "'" . $barcode . "', ". "'" . $bookname . "', ". "'" . $volumenum . "', ". "'" . $author . "', ". "'" . $publisher . "', ". "'" . $itemtype . "', ". "'" . $buyprice . "', ". "'" . getMySQLDateString($buydate). //"'STR_TO_DATE('".$buydate ."', '%d/%m/%Y'))'". //nothing changes in MySQL ")"); And this is the faulty function : function getMySQLDateString($buydate) //typical buydate : 04/21/2009 { $mysqlDateString = date('Y-m-d H:i:s', $strtotime($buydate)); return $mysqlDateString; } The first commented out line wouldn't do anything, the script is executed with no error, however, there is nothing changed in datebase after this. The current approach will cause a Fatal error saying function name must be a string in this line. Actually I followed this thread on SO, but just cannot pass the date into MySQL... Can anyone help me figure out which part is not right? How would you do it, in this case, to get it right? Sorry about such a journeyman-like question, thanks a lot in advance.

    Read the article

  • MySQL don't want to store unicode charecter

    - by Qiao
    Why MySQl don't wont to store unicode character ??? Yes, it is rare hieroglyph, you wouldn't see it in the browser. UTF16 is U+2B5EE Warning: #1366 Incorrect string value: '\xF0\xAB\x97\xAE' for column 'ch' at row 1 Is it possible to store this character in MySQL?

    Read the article

  • When should I use MySQL compressed protocol?

    - by ento
    I've learned that MySQL can compress communication between servers and clients. Compression is used if both client and server support zlib compression, and the client requests compression. (from MySQL Forge Wiki) The most obvious pros and cons are pros: Reduced payload size cons: Increased computation time So, is compressed protocol something I should enable whenever I can afford servers with adequate specs? Are there other factors I should consider?

    Read the article

  • Table prefix for MySqlMembershipProvider

    - by choudeshell
    I have MySqlMembershipProvider working with Asp.Net MVC. My question is how can I configure the table prefix... so instead of 'my_aspnet_' prefix on the tables, I want this to be either none or defined by me. My web.config: <?xml version="1.0"?> <add name="ApplicationServices" connectionString="server=localhost;user id=root;Password=*********;database=sparkSources" providerName="MySql.Data.MySqlClient"/> <authentication mode="Forms"> <forms loginUrl="~/Account/LogOn" timeout="2880" /> </authentication> <membership defaultProvider="MySqlMembershipProvider"> <providers> <clear/> <add name="MySqlMembershipProvider" type="MySql.Web.Security.MySQLMembershipProvider, MySql.Web, Version=6.3.4.0, Culture=neutral, PublicKeyToken=c5687fc88969c44d" autogenerateschema="true" tablePrefix="ss" connectionStringName="ApplicationServices" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" passwordFormat="Hashed" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" passwordStrengthRegularExpression="" applicationName="sparkSources" /> </providers> </membership> <profile> <providers> <clear/> <add name="AspNetSqlProfileProvider" type="System.Web.Profile.SqlProfileProvider" connectionStringName="ApplicationServices" applicationName="/" /> </providers> </profile> <roleManager enabled="false"> <providers> <clear/> <add name="AspNetSqlRoleProvider" type="System.Web.Security.SqlRoleProvider" connectionStringName="ApplicationServices" applicationName="/" /> <add name="AspNetWindowsTokenRoleProvider" type="System.Web.Security.WindowsTokenRoleProvider" applicationName="/" /> </providers> </roleManager> <pages> <namespaces> <add namespace="System.Web.Mvc" /> <add namespace="System.Web.Mvc.Ajax" /> <add namespace="System.Web.Mvc.Html" /> <add namespace="System.Web.Routing" /> </namespaces> </pages>

    Read the article

  • Do entity collections and object sets implement IQueryable<T>?

    - by Chevex
    I am using Entity Framework for the first time and noticed that the entities object returns entity collections. DBEntities db = new DBEntities(); db.Users; //Users is an ObjectSet<User> User user = db.Users.Where(x => x.Username == "test").First(); //Is this getting executed in the SQL or in memory? user.Posts; //Posts is an EntityCollection<Post> Post post = user.Posts.Where(x => x.PostID == "123").First(); //Is this getting executed in the SQL or in memory? Do both ObjectSet and EntityCollection implement IQueryable? I am hoping they do so that I know the queries are getting executed at the data source and not in memory. EDIT: So apparently EntityCollection does not while ObjectSet does. Does that mean I would be better off using this code? DBEntities db = new DBEntities(); User user = db.Users.Where(x => x.Username == "test").First(); //Is this getting executed in the SQL or in memory? Post post = db.Posts.Where(x => (x.PostID == "123")&&(x.Username == user.Username)).First(); // Querying the object set instead of the entity collection. Also, what is the difference between ObjectSet and EntityCollection? Shouldn't they be the same? Thanks in advance!

    Read the article

  • how to store a 2D game world in mysql

    - by monthon1
    I am making a 2D game in javascript/ajax, that will be using data stored in mysql database. Every user have got his own "area" made of small squares that can have some values. But I have no idea, how to store values of each square in mysql, when each user can have area with different width or height. Do you have some idea?

    Read the article

  • Problem installing mysql 5 on Ubuntu 10.10

    - by mujer esponja
    Hello! In my Ubuntu 10.10, following this tutorial, I don't face step 2. I mean, while installing the packets, I don't face anything related to configuration. Then, when I run a command, such a mysql -u root -p , I get this error: ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) As I see in other treads, ps aux | grep mysqld gives me just this output: 1000 4508 0.0 0.0 5172 760 pts/0 S+ 19:53 0:00 grep --color=auto mysqld What is happening?? Thanks in advance

    Read the article

  • Multiple values one field mysql

    - by chloe
    Basically I have a a mysql database which i want to create containing the following tables: artist song album A song can belong to only one artist, however, a song could be in Multiple Albums. How would I go about implementing this in my mysql database. I've been stuck for a few days now :(

    Read the article

< Previous Page | 134 135 136 137 138 139 140 141 142 143 144 145  | Next Page >