Search Results

Search found 5407 results on 217 pages for 'surrogate keys'.

Page 39/217 | < Previous Page | 35 36 37 38 39 40 41 42 43 44 45 46  | Next Page >

• Foreign key constraints in Android using SQLite? on Delete cascade.

  - by LordSnoutimus

  I have two tables: tracks and waypoints, a track can have many waypoints, but a waypoint is assigned to only 1 track. In the way points table I have a column called "trackidfk" which inserts the track_ID once a track is made, however I have not setup Foreign Key constraints on this column. When I delete a track I want to delete the assigned waypoints, is this possible?. I read about using Triggers but I don't think they are supported in Android. To create the waypoints table: public void onCreate(SQLiteDatabase db) { db.execSQL("CREATE TABLE " + TABLE_NAME + " (" + _ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + LONGITUDE + " INTEGER," + LATITUDE + " INTEGER," + TIME + " INTEGER,"+ TRACK_ID_FK + " INTEGER );");

  Read the article

• Sorting a Multidimensional array...

  - by sologhost

  I need to sort an array that can look like this: $array[4][0] = array('id' => 1, 'value' => 2); $array[3][2] = array('id' => 0, 'value' => 3); $array[4][1] = array('id' => 1, 'value' => 0); $array[1][3] = array('id' => 2, 'value' => 1); $array[1][1] = array('id' => 3, 'value' => 0); $array[3][0] = array('id' => 2, 'value' => 1); $array[3][1] = array('id' => 1, 'value' => 0); $array[1][2] = array('id' => 3, 'value' => 2); $array[1][0] = array('id' => 2, 'value' => 1); $array[2][1] = array('id' => 0, 'value' => 2); $array[2][4] = array('id' => 3, 'value' => 1); But needs to be sorted and returned as this: $array[1][0] = array('id' => 2, 'value' => 1); $array[1][1] = array('id' => 3, 'value' => 0); $array[1][2] = array('id' => 3, 'value' => 2); $array[1][3] = array('id' => 2, 'value' => 1); $array[2][1] = array('id' => 0, 'value' => 2); $array[2][4] = array('id' => 3, 'value' => 1); $array[3][0] = array('id' => 2, 'value' => 1); $array[3][1] = array('id' => 1, 'value' => 0); $array[3][2] = array('id' => 0, 'value' => 3); $array[4][0] = array('id' => 1, 'value' => 2); $array[4][1] = array('id' => 1, 'value' => 0); Can anyone help me? It needs to sort both indexes of the array from lowest to highest index value. Sounds simple enough, but I'm having the hardest time trying to figure this out, while still keeping the values intact. Please help someone...

  Read the article

• MySQL Error 1452 - Cannot add or update a child row: a foreign key constraint fails

  - by dscher

  I've looked at other people's questions on this topic but can't seem to find where my error is coming from. Any help would be greatly appreciated. I'm including as much as I can think of that might help find the problem: CREATE TABLE stocks ( id INT AUTO_INCREMENT NOT NULL, user_id INT(11) UNSIGNED NOT NULL, ticker VARCHAR(20) NOT NULL, name VARCHAR(20), rating INT(11), position ENUM("strong buy", "buy", "sell", "strong sell", "neutral"), next_look DATE, privacy ENUM("public", "private"), PRIMARY KEY(id), FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE IF NOT EXISTS `stocks_tags` ( `stock_id` INT NOT NULL, `tag_id` INT NOT NULL, PRIMARY KEY (`stock_id`,`tag_id`), KEY `fk_stock_tag` (`tag_id`), KEY `fk_tag_stock` (`stock_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; ALTER TABLE `stocks_tags` ADD CONSTRAINT `fk_stock_tag` FOREIGN KEY (`tag_id`) REFERENCES `tags` (`id`) ON DELETE CASCADE ON UPDATE CASCADE, ADD CONSTRAINT `fk_tag_stock` FOREIGN KEY (`stock_id`) REFERENCES `stocks` (`id`) ON DELETE CASCADE ON UPDATE CASCADE; CREATE TABLE tags( id INT AUTO_INCREMENT NOT NULL PRIMARY KEY, tags VARCHAR(30), UNIQUE(tags) ) ENGINE=INNODB DEFAULT CHARSET=utf8; And the error I'm getting: Database_Exception [ 1452 ]: Cannot add or update a child row: a foreign key constraint fails (`ddmachine`.`stocks_tags`, CONSTRAINT `fk_stock_tag` FOREIGN KEY (`tag_id`) REFERENCES `tags` (`id`) ON DELETE CASCADE ON UPDATE CASCADE) [ INSERT INTO `stocks_tags` (`stock_id`, `tag_id`) VALUES (19, 'cash') ] I did see that someone else had a similar problem based on their enum columns but don't think that's it.

  Read the article

• ASP MVC C#: LINQ Foreign Key Constraint conflicts

  - by wh0emPah

  I'm having a problem with LINQ. I have 2 tables (Parent-child relation) Table1: Events (EventID, Description) Table2: Groups (GroupID, EventID(FK), Description) Now i want to create an Event an and a child. Event e = new Event(); e.Description = "test"; Datacontext.Events.InsertOnSubmit(event) Group g = new Group(); g.Description = "test2"; g.EventID = e.EventID; Datacontext.Groups.InsertOnSubmit(g); Datacontext.SubmitChanges(); When i debug, i can see that after inserting the event. the EventID has gotten a new value (auto increment). But when Datacontext.SubmitChanges(); gets called. I get the following exception "The INSERT statement conflicted with the FOREIGN KEY constraint ... I know this can be solved by creating a relation in the LINQ diagram between Events and groups. And then setting the entity itself. But i don't want to load the events everytime i ask a list of groups. All i need is some way that when inserting the group fails, the event insert won't be comitted in the database. Sorry if this is a bit unclear, My english isn't really good. Thanks in advance!

  Read the article

• Fluent composite foreign key mapping

  - by Fionn

  Hi, I wonder if this is possible to map the following with fluent nhibernate: A document table and a document_revision table will be the target tables. The document_revision table should have a composite unique key consisting of the document_id and the revision number (where the document_id is also the foreign key to the document table). class Document { Guid Id; //other members omitted } class DocumentRevision { Guid document_id; //Part one of the primary key and also foreign key to Document.Id int revision; //Part two of the primary key //other members omitted }

  Read the article

• Does any SQL frontend display subdatasheets like Access?

  - by Jeremy Rudd

  I'm looking for an SQL client app that can display subdatasheets like the following: Do you know of any?

  Read the article

• Why does a user have to enter "Profile" data to enter data into other tables?

  - by Greg McNulty

  EDIT It appears the user has to enter some data for his profile, otherwise I get this error below. I guess if there is no profile data, the user can not continue to enter data in other tables by default? I do not want to make entering user profile data a requirement to use the rest of the sites functionality, how can I get around this? Currently I have been testing everything with the same user and everything has been working fine. However, when I created a new user for the very first time and tried to enter data into my custom table, I get the following error. The INSERT statement conflicted with the FOREIGN KEY constraint "FK_UserData_aspnet_Profile". The conflict occurred in database "C:\ISTATE\APP_DATA\ASPNETDB.MDF", table "dbo.aspnet_Profile", column 'UserId'. The statement has been terminated. Not sure why I am getting this error. I have the user controls set up in ASP.NET 3.5 however all I am using is my own table or at least that I am aware of. I have a custom UserData table that includes the columns: id, UserProfileID, CL, LL, SL, DateTime (id is the auto incremented int) The intent is that all users will add their data in this table and as I mentioned above it has been working fine for my original first user I created. However, when i created a new user I am getting this problem. Here is the code that updates the database. protected void Button1_Click(object sender, EventArgs e) { //connect to database MySqlConnection database = new MySqlConnection(); database.CreateConn(); //create command object Command = new SqlCommand(queryString, database.Connection); //add parameters. used to prevent sql injection Command.Parameters.Add("@UID", SqlDbType.UniqueIdentifier); Command.Parameters["@UID"].Value = Membership.GetUser().ProviderUserKey; Command.Parameters.Add("@CL", SqlDbType.Int); Command.Parameters["@CL"].Value = InCL.Text; Command.Parameters.Add("@LL", SqlDbType.Int); Command.Parameters["@LL"].Value = InLL.Text; Command.Parameters.Add("@SL", SqlDbType.Int); Command.Parameters["@SL"].Value = InSL.Text; Command.ExecuteNonQuery(); } Source Error: Line 84: Command.ExecuteNonQuery();

  Read the article

• Hostgator SSH returns Too many authentication failures for username

  - by Tri Nguyen

  I was trying to ssh into my Hostgator shared hosting account following this guide: http://support.hostgator.com/articles/getting-started/how-do-i-get-and-use-ssh-access However, it returns this error: Received disconnect from 96.125.167.124: 2: Too many authentication failures for tridn I tried to search around for a solution, and found this: http://www.ipreferjim.com/2011/07/hostgator-ssh-warns-too-many-authentication-failures/ I tried doing what he suggested, but encountered another error: jailshell: .ssh/authorized_keys: No such file or directory So I ssh into my server using the PubkeyAuthentication=n flag, and create a directory called .ssh and a file called authorized_keys. I then redid what was suggested in the article, which is this: cat ~/.ssh/hostgator.pub | ssh -p 2222 -o PubkeyAuthentication=no [email protected] 'cat >> .ssh/authorized_keys' (note: my ssh key is called hostgator.pub. it's dsa I verified that the authorized_keys now has the content of this key. However, it still get the same error as before: eceived disconnect from 96.125.167.124: 2: Too many authentication failures for tridn Anybody knows how I should proceed next?

  Read the article

• Merge replication server side foreign key violation from unpublished table

  - by Reiste

  We are using SQL Server 2005 Merge Replication with SQL CE 3.5 clients. We are using partitions with filtering for the separate subscriptions, and nHibernate for the ORM mapping. There is automatic ID range management from SQL Server for the subscriptions. We have a table, Item, and a table with a foreign key to Item - ItemHistory. Both of these are replicated down, filtered according to the subscription. Item has a column called UserId, and is filtered per subscription with this filter: WHERE UserId IN (SELECT... [complicated subselect]...) ItemHistory hangs off Item in the publication filter articles. On the server, we have a table ItemHistoryExport, which has a foreign key to ItemHistory. ItemHistoryExport is not published. Entries in the Item and ItemHistory tables are never deleted, on the server or the client. However, the "ownership" of items (and hence their ItemHistories) MAY change, which causes them to be moved from one client subscription/partition to another from time to time. When we sync, we occasionally get the following error: A row delete at '48269404 - 4108383dbb11' could not be propagated to 'MyServer\MyInstance.MyDatabase'. This failure can be caused by a constraint violation. The DELETE statement conflicted with the REFERENCE constraint "FK_ItemHistoryExport_ItemHistory". The conflict occurred in database "MyDatabase", table "dbo.ItemHistoryExport", column 'ItemHistoryId'. Can anyone help us understand why this happens? There shouldn't ever be a delete happening on the server side.

  Read the article

• hibernate foreign key mapping many-to-one

  - by Lily

  I have been working on it for quite a while, but still can't figure out what's wrong with my code. Each Service has multiple profiles, but each profile only has one Service. Service { Long service_id; // primary key ... getter/setter } Profile { Long profile_id; // primary key Long service_id; // foreign key ... getter and setter } in Profile.hbm.xml. I add < many-to-one name="service_id" class="com.mot.diva.dto.Service" column="SERVICE_ID" cascade="save-update"> < /many-to-one> Is it the correct way to map it?

  Read the article

• Limit foreign key choices in select in an inline form in admin

  - by mightyhal

  Edited :-) Hopefully a bit clearer now. The logic is of the model is: A Building has many Rooms A Room may be inside another Room (a closet, for instance--ForeignKey on 'self') A Room can only in inside of another Room in the same building (this is the tricky part) Here's the code I have: #spaces/models.py from django.db import models class Building(models.Model): name=models.CharField(max_length=32) def __unicode__(self): return self.name class Room(models.Model): number=models.CharField(max_length=8) building=models.ForeignKey(Building) inside_room=models.ForeignKey('self',blank=True,null=True) def __unicode__(self): return self.number and: #spaces/admin.py from ex.spaces.models import Building, Room from django.contrib import admin class RoomAdmin(admin.ModelAdmin): pass class RoomInline(admin.TabularInline): model = Room extra = 2 class BuildingAdmin(admin.ModelAdmin): inlines=[RoomInline] admin.site.register(Building, BuildingAdmin) admin.site.register(Room) The inline will display only rooms in the current building (which is what I want). The problem, though, is that for the inside_room drop down, it displays all of the rooms in the Rooms table (including those in other buildings). In the inline of rooms, I need to limit the inside_room choices to only rooms which are in the current building being displayed by the main form. I can't figure out a way to do it with either a limit_choices_to in the model, nor can I figure out how exactly to override the admin's inline formset properly (I feel like I should be somehow create a custom inline form, pass the building_id of the main form to the custom inline, then limit the queryset for the field's choices based on that--but I just can't wrap my head around how to do it). Maybe this is too complex for the admin site, but it seems like something that would be generally useful... Thanks again for your help!

  Read the article

• MS-Access: What could cause one form with a join query to load right and another not?

  - by Daniel Straight

  Form1 Form1 is bound to Table1. Table1 has an ID field. Form2 Form2 is bound to Table2 joined to Table1 on Table2.Table1_ID=Table1.ID Here is the SQL (generated by Access): SELECT Table2.*, Table1.[FirstFieldINeed], Table1.[SecondFieldINeed], Table1.[ThirdFieldINeed] FROM Table1 INNER JOIN Table2 ON Table1.ID = Table2.[Table1_ID]; Form2 is opened with this code in Form1: DoCmd.RunCommand acCmdSaveRecord DoCmd.OpenForm "Form2", , , , acFormAdd, , Me.[ID] DoCmd.Close acForm, "Form1", acSaveYes And when loaded runs: Me.[Table1_ID] = Me.OpenArgs When Form2 is loaded, fields bound to columns from Table1 show up correctly. Form3 Form3 is bound to Table3 joined to Table2 on Table3.Table2_ID=Table2.ID Here is the SQL (generated by Access): SELECT Table3.*, Table2.[FirstFieldINeed], Table2.[SecondFieldINeed] FROM Table2 INNER JOIN Table3 ON Table2.ID = Table3.[Table2_ID]; Form3 is opened with this code in Form2: DoCmd.RunCommand acCmdSaveRecord DoCmd.OpenForm "Form3", , , , acFormAdd, , Me.[ID] DoCmd.Close acForm, "Form2", acSaveYes And when loaded runs: Me.[Table2_ID] = Me.OpenArgs When Form3 is loaded, fields bound to columns from Table2 do not show up correctly. WHY? UPDATES I tried making the join query into a separate query and using that as my record source, but it made no difference at all. If I go to the query for Form3 and view it in datasheet view, I can see that the information that should be pulled into the form is there. It just isn't showing up on the form.

  Read the article

• SQL server deadlock between INSERT and SELECT statement

  - by dtroy

  Hi! I've got a problem with multiple deadlocks on SQL server 2005. This one is between an INSERT and a SELECT statement. There are two tables. Table 1 and Table2. Table2 has Table1's PK (table1_id) as foreign key. Index on table1_id is clustered. The INSERT inserts a single row into table2 at a time. The SELCET joins the 2 tables. (it's a long query which might take up to 12 secs to run) According to my understanding (and experiments) the INSERT should acquire an IS lock on table1 to check referential integrity (which should not cause a deadlock). But, in this case it acquired an IX page lock The deadlock report: <deadlock-list> <deadlock victim="process968898"> <process-list> <process id="process8db1f8" taskpriority="0" logused="2424" waitresource="OBJECT: 5:789577851:0 " waittime="12390" ownerId="61831512" transactionname="user_transaction" lasttranstarted="2010-04-16T07:10:13.347" XDES="0x222a8250" lockMode="IX" schedulerid="1" kpid="3764" status="suspended" spid="52" sbid="0" ecid="0" priority="0" transcount="2" lastbatchstarted="2010-04-16T07:10:13.350" lastbatchcompleted="2010-04-16T07:10:13.347" clientapp=".Net SqlClient Data Provider" hostname="VIDEV01-B-ME" hostpid="3040" loginname="DatabaseName" isolationlevel="read uncommitted (1)" xactid="61831512" currentdb="5" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056"> <executionStack> <frame procname="DatabaseName.dbo.prcTable2_Insert" line="18" stmtstart="576" stmtend="1148" sqlhandle="0x0300050079e62d06e9307f000b9d00000100000000000000"> INSERT INTO dbo.Table2 ( f1, table1_id, f2 ) VALUES ( @p1, @p_DocumentVersionID, @p1 ) </frame> </executionStack> <inputbuf> Proc [Database Id = 5 Object Id = 103671417] </inputbuf> </process> <process id="process968898" taskpriority="0" logused="0" waitresource="PAGE: 5:1:46510" waittime="7625" ownerId="61831406" transactionname="INSERT" lasttranstarted="2010-04-16T07:10:12.717" XDES="0x418ec00" lockMode="S" schedulerid="2" kpid="1724" status="suspended" spid="53" sbid="0" ecid="0" priority="0" transcount="2" lastbatchstarted="2010-04-16T07:10:12.713" lastbatchcompleted="2010-04-16T07:10:12.713" clientapp=".Net SqlClient Data Provider" hostname="VIDEV01-B-ME" hostpid="3040" loginname="DatabaseName" isolationlevel="read committed (2)" xactid="61831406" currentdb="5" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056"> <executionStack> <frame procname="DatabaseName.dbo.prcGetList" line="64" stmtstart="3548" stmtend="11570" sqlhandle="0x03000500dbcec17e8d267f000b9d00000100000000000000"> <!-- XXXXXXXXXXXXXX...SELECT STATEMENT WITH Multiple joins including both Table2 table 1 and .... XXXXXXXXXXXXXXX --> </frame> </executionStack> <inputbuf> Proc [Database Id = 5 Object Id = 2126630619] </inputbuf> </process> </process-list> <resource-list> <pagelock fileid="1" pageid="46510" dbid="5" objectname="DatabaseName.dbo.table1" id="lock6236bc0" mode="IX" associatedObjectId="72057594042908672"> <owner-list> <owner id="process8db1f8" mode="IX"/> </owner-list> <waiter-list> <waiter id="process968898" mode="S" requestType="wait"/> </waiter-list> </pagelock> <objectlock lockPartition="0" objid="789577851" subresource="FULL" dbid="5" objectname="DatabaseName.dbo.Table2" id="lock970a240" mode="S" associatedObjectId="789577851"> <owner-list> <owner id="process968898" mode="S"/> </owner-list> <waiter-list> <waiter id="process8db1f8" mode="IX" requestType="wait"/> </waiter-list> </objectlock> </resource-list> </deadlock> </deadlock-list> Can anyone explain why the INSERT gets the IX page lock ? Am I not reading the deadlock report properly? BTW, I have not managed to reproduce this issue. Thanks!

  Read the article

• Which MySQL Frontend shows foreign rows?

  - by Jeremy Rudd

  I once came across a MySQL Frontend app that displayed foreign linked rows within the parent row, if for instance the Events table has a foreign key to the Students table: Student ID Name DOB -- ---- --------- [+] 22 Bob 25-1-1984 [-] 21 Jane 25-1-1982 Event ID Student-ID Name Time -- ---------- ---- --------- 1 21 Event A 05:50 1 21 Event B 17:20 [+] 20 Jack 25-1-1980

  Read the article

• EF4 CTP5 - Map foreign key without object references?

  - by anon

  I feel like this should have a simple answer, but I can't find it. I have 2 POCOs: public class Category { public int Id { get; set; } public string Name { get; set; } } public class Product { public int Id { get; set; } public int CategoryId { get; set; } } Notice that there are no object references on either POCO. With Code-First, how do I make EF4 CTP5 define a relationship between the two database tables? (I know this is an unusual scenario, but I am exploring what's possible and what's not with Code-First)

  Read the article

• Keybd is not working right =(

  - by user302131

  i can't get this to work right this should press left for 1sec then wait 10secs then right 1sec. keybd_event(0x25, 0xCB, 0, 0); // press left cout << "Ldown\n"; // so i know it worked Sleep(1000); // hold it for 1sec keybd_event(0x25, 0xCB, KEYEVENTF_KEYUP, 0);// let go of the key cout << "Lup\n"; // so i know i let go Sleep(10000); // Sleep for 10secs keybd_event(0x27, 0xCD, 0, 0); // press right cout << "Rdown\n"; // so i know i pressed right Sleep(1000); // sleep 1sec keybd_event(0x27, 0xCD, KEYEVENTF_KEYUP, 0);// let go of the key cout << "Rdown\n"; // so i know i let go. this is in a loop but it wont do anything :( unless i close the program before the key is let go then it will just keep the keydown until i press the key again. i know you can use only one key code if you want but i need to use both. so what i'm i missing?

  Read the article

• Pros and cons of programmatically enforcing foreign key than in database

  - by Jeffrey

  It is causing so much trouble in terms of development just by letting database enforcing foreign key. Especially during unit test I can’t drop table due to foreign key constrains, I need to create table in such an order that foreign key constrain warning won’t get triggered. In reality I don’t see too much point of letting database enforcing the foreign key constrains. If the application has been properly designed there should not be any manual database manipulation other than select queries. I just want to make sure that I am not digging myself into a hole by not having foreign key constrains in database and leaving it solely to the application’s responsibility. Am I missing anything? P.S. my real unit tests (not those that use mocking) will drop existing tables if the structure of underlying domain object has been modified.

  Read the article

• Foreign key,local key?

  - by user198729

  CREATE TABLE products ( id integer unsigned auto_increment primary key ) ENGINE=INNODB; CREATE TABLE orders ( id integer PRIMARY KEY auto_increment, product_id integer unsigned, quantity integer, INDEX product_id_idx (product_id), FOREIGN KEY (product_id) REFERENCES products (id) ) ENGINE=INNODB; Here the products and orders obviously have some kind of relation--foreign key relation. Also a coin has two sides,so I'm doubting how do we say which table is the foreign key side or local key side?

  Read the article

• Drop primary key index

  - by Ruwani

  Can I drop primary key index without dropping primary key constraint in postgresql?

  Read the article

• SSAS Cube reprocessing fails - then succeeds if I try again

  - by EdgarVerona

  So I'm basically brand new to the concept of BI, and I've inherited an existing ETL process that is a two step process: 1) Loads the data into a database that is only used by the cube processing 2) Starts off the SSAS cube processing against said database It seems pretty well isolated, but occasionally (once a week, sometimes twice) it will fail with the following exception: "Errors in the OLAP storage engine: The attribute key cannot be found" Now the interesting thing is that: 1) The dimension having the issue is not usually the same one (i.e. there's no single dimension that consistently has this failure) 2) The source table, when I inspect it, does actually contain the attribute key that it says could not be found And, most interestingly... 3) If I then immediately reprocess the dimensions and cubes manually through SSMS, they reprocess successfully and without incident. In both the aforementioned job and when I reprocess them through SSMS, I am using "ProcessFull", so it should be reprocessing them completely. Has anyone run into such an issue? I'm scratching my head about it... because if it was a genuine data integrity issue, reprocessing the cube again wouldn't fix it. What on earth could be happening? I've been tasked with finding out why this happens, but I can neither reproduce it consistently nor can I point to a data integrity problem as the root cause. Thanks for any input you can provide!

  Read the article

• How to generate SSH key pairs with Python

  - by Lee

  Hello, I'm attempting to write a script to generate SSH Identity key pairs for me. from M2Crypto import RSA key = RSA.gen_key(1024, 65337) key.save_key("/tmp/my.key", cipher=None) The file /tmp/my.key looks great now. By running ssh-keygen -y -f /tmp/my.key > /tmp/my.key.pub I can extract the public key. My question is how can I extract the public key from python? Using key.save_pub_key("/tmp/my.key.pub") saves something like: -----BEGIN PUBLIC KEY----- MFwwDQYJKoZIhvcNAQEBBQADASDASDASDASDBarYRsmMazM1hd7a+u3QeMP ... FZQ7Ic+BmmeWHvvVP4Yjyu1t6vAut7mKkaDeKbT3yiGVUgAEUaWMXqECAwEAAQ== -----END PUBLIC KEY----- When I'm looking for something like: ssh-rsa AAAABCASDDBM$%3WEAv/3%$F ..... OSDFKJSL43$%^DFg==

  Read the article

• How do I delete a foreign key in SQLAlchemy?

  - by Travis

  I'm using SQLAlchemy Migrate to keep track of database changes and I'm running into an issue with removing a foreign key. I have two tables, t_new is a new table, and t_exists is an existing table. I need to add t_new, then add a foreign key to t_exists. Then I need to be able to reverse the operation (which is where I'm having trouble). t_new = sa.Table("new", meta.metadata, sa.Column("new_id", sa.types.Integer, primary_key=True) ) t_exists = sa.Table("exists", meta.metadata, sa.Column("exists_id", sa.types.Integer, primary_key=True), sa.Column( "new_id", sa.types.Integer, sa.ForeignKey("new.new_id", onupdate="CASCADE", ondelete="CASCADE"), nullable=False ) ) This works fine: t_new.create() t_exists.c.new_id.create() But this does not: t_exists.c.new_id.drop() t_new.drop() Trying to drop the foreign key column gives an error: 1025, "Error on rename of '.\my_db_name\#sql-1b0_2e6' to '.\my_db_name\exists' (errno: 150)" If I do this with raw SQL, i can remove the foreign key manually then remove the column, but I haven't been able to figure out how to remove the foreign key with SQLAlchemy? How can I remove the foreign key, and then the column?

  Read the article

• How to set public SSH key for root user on server?

  - by amrnt

  I'm trying to follow Slicehost Document to setup my server. I reached SSH section. I made it as written, but when i logged out from root, i cant access root@IP_ADDRESS -p 30000 again! but i can access user@IP_ADDRESS -p 30000. So, the question is, how to set a public SSH key for root user? Thanks in advance!

  Read the article

• What key on a keyboard can be detected in the browser but won't show up in a text input?

  - by Brady

  I know this one is going to sound weird but hear me out. I have a heart rate monitor that is hooked up like a keyboard to the computer. Each time the heart rate monitor detects a pulse it sends a key stroke. This keystroke is then detected by a web based game running in the browser. Currently I'm sending the following keystroke: (`) In the browser base game I'm detecting the following key fine and if when the user is on any data input screens the (`) character is ignored using a bit of JavaScript. The problem comes when I leave the browser and go back to using the Operating system in other ways the (`) starts appearing everywhere. So my question is: Is there a key that can be sent via the keyboard that is detectable in the browser but wont have any notable output on the screen if I switch to other applications. I'm kind of looking for a null key. A key that is detectable in the browser but has no effect to the browser or any other system application if pressed.

  Read the article

• Django: many-to-one fields and data integrity

  - by John

  Let's say that I have a Person who runs an inventory system. Each Person has some Cars, and each Car has a very large number of Parts (thousands, let's say). A Person, Bob, uses a Django form to create a Car. Now, Bob goes to create some Parts. It is only at the form level that Django knows that the Parts belong to some specific Car, and that the Parts.ForeignKey(Car) field should only have a specific Car as a choice. When creating a Part, you have to mess with the form's constructor or similar in order to limit the choice of Cars to only the cars owned by Bob. It does not seem proper that to enforce this ownership at the form level. It seems that other users' Cars must be inaccessible to anyone but the owner of the Car. What do you all think about this, and is there any way to enforce this?

  Read the article

< Previous Page | 35 36 37 38 39 40 41 42 43 44 45 46  | Next Page >