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  • Use a foreign key mapping to get data from the other table using Python and SQLAlchemy.

    - by Az
    Hmm, the title was harder to formulate than I thought. Basically, I've got these simple classes mapped to tables, using SQLAlchemy. I know they're missing a few items but those aren't essential for highlighting the problem. class Customer(object): def __init__(self, uid, name, email): self.uid = uid self.name = name self.email = email def __repr__(self): return str(self) def __str__(self): return "Cust: %s, Name: %s (Email: %s)" %(self.uid, self.name, self.email) The above is basically a simple customer with an id, name and an email address. class Order(object): def __init__(self, item_id, item_name, customer): self.item_id = item_id self.item_name = item_name self.customer = None def __repr__(self): return str(self) def __str__(self): return "Item ID %s: %s, has been ordered by customer no. %s" %(self.item_id, self.item_name, self.customer) This is the Orders class that just holds the order information: an id, a name and a reference to a customer. It's initialised to None to indicate that this item doesn't have a customer yet. The code's job will assign the item a customer. The following code maps these classes to respective database tables. # SQLAlchemy database transmutation engine = create_engine('sqlite:///:memory:', echo=False) metadata = MetaData() customers_table = Table('customers', metadata, Column('uid', Integer, primary_key=True), Column('name', String), Column('email', String) ) orders_table = Table('orders', metadata, Column('item_id', Integer, primary_key=True), Column('item_name', String), Column('customer', Integer, ForeignKey('customers.uid')) ) metadata.create_all(engine) mapper(Customer, customers_table) mapper(Orders, orders_table) Now if I do something like: for order in session.query(Order): print order I can get a list of orders in this form: Item ID 1001: MX4000 Laser Mouse, has been ordered by customer no. 12 What I want to do is find out customer 12's name and email address (which is why I used the ForeignKey into the Customer table). How would I go about it?

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  • How do I use a MySQL subquery to count the number of rows in a foreign table?

    - by James Skidmore
    I have two tables, users and reports. Each user has no, one, or multiple reports associated with it, and the reports table has a user_id field. I have the following query, and I need to add to each row a count of how many reports the user has: SELECT * FROM users LIMIT 1, 10 Do I need to use a subquery, and if so, how can I use it efficently? The reports table has thousands and thousands of rows.

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  • How do I specify the foreign key on a many-to-one relationship when is not a property on the object

    - by jjujuma
    I'm trying to map a many-to-one relationship from MarketMenuBranch to Market. My classes look like: public class Market implements Serializable { private int id; private String name; private List<MarketMenuBranch> marketMenuBranches; // accessors / mutators etc... public class MarketMenuBranch implements Serializable { private MarketMenuBranchId id; private String name; // accessors / mutators etc... public class MarketMenuBranchId implements Serializable { private int marketId; private int sequence; // accessors / mutators etc... But I don't know what I can put for the property name (where I have ???? below). I really want to put id.marketId but that seems to be wrong. <class name="MarketMenuBranch" table="MARKET_MENU_BRANCH"> <composite-id name="id" class="MarketMenuBranchId"> <key-property name="marketId"/> <key-property name="sequence"/> </composite-id> <property name="name"/> <many-to-one name="????????"/> </class> How can I do this?

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  • Rails 3: Create an instance with 3 foreign keys.

    - by donald
    Hello, Having a reviews table: # Table name: reviews # # id :integer not null, primary key # wsp_id :integer # service_id :integer # user_id :integer # description :text # rating :integer # created_at :datetime # updated_at :datetime # belongs_to :wsp belongs_to :service belongs_to :user How can I create a review for a service and pass the wsp_id and user_id? Do I need to use nested routes? I am able to do @user.reviews.new(params[:review]) but I'm not being able of passing the wsp_id and the service_id. Here's my Reviews create controller. def create @review = current_user.reviews.new(params[:review]) if @review.save #Saved else #Error, not saved end end What am I doing wrong? Thank you!

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  • How do I define a foreign key that points to a class of a different name in ActiveRecord with Rails?

    - by Mark
    Hi there, I have a model Follow that defines a user_id and a followed_user_id. If you've used Twitter, this should make sense. I'm trying to make followed_user_id point to a User model, so I can access the user that is being followed through f.followed_user (in the same way that if I have an Entry with belongs_to :user and a user_id column I can use entry.user to get the user.) How can I do this? Thanks!

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  • Windows "forms" authentication - <deny users="?"> redirecting to foreign page!

    - by Erik5388
    Like the title states - I have a web.config file that looks like, <?xml version="1.0" encoding="UTF-8"?> <configuration> <system.web> <compilation debug="true" targetFramework="4.0" /> <authentication mode="Forms"> <forms name="login" protection="All" timeout="30" loginUrl="login" defaultUrl="~/"> <credentials passwordFormat="Clear"> <user name="admin" password="password" /> </credentials> </forms> </authentication> <authorization> <deny users="?" /> </authorization> </system.web> </configuration> I want to do exactly what it says it should do... I want to deny all users who try to enter the site. It works however, it redirects to a "Account/Login?ReturnUrl=%2flogin" url I have never heard of... Is there a place I can change this?

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  • EF Code First, how can I achieve two foreign keys from one table to other table?

    - by Yoo Matsuo
    I've recently downloaded Entity Framework Code First CTP5, and have a trouble with this scenario. I have two tables as follows: Members table ID Name Comments table ID Comment CommentedMemberID CommentMemberID And, the data should be like the following: Members ID Name 1 Mike 2 John 3 Tom Comments ID Comment CommentedMemberID CommentMemberID 1 Good 1 2 2 Good 1 3 3 Bad 2 1 Then, I coded as shown below: public class Member { public int ID {get; set; } public string Name { get; set;} public virtual ICollection Comments { get; set;} } public class Comment { public int ID { get; set; } public string Comment { get; set; } public int CommentedMemberID { get; set; } public int CommentMemberID{ get; set; } public virtual Member CommentedMember { get; set; } public virtual Member CommentMember { get; set; } } public class TestContext : DbContext { public DbSet Members { get; set; } public DbSet Comments { get; set; } } But when I run these models on my cshtml, it gives me errors saying "Cannot create CommentMember instance" or something like that (Sorry, I already changed my models to proceed the EF Code First evaluation, so can't reproduce the same error). I've also tried to use OnModelCreating on the TestContext, but can't find any good instructions and don't know what to do. I saw a blog post of the EF Code First CTP3, and it seems there was a RelatedTo attribute in that version, but now it has gone. Could anyone know how to get it work properly? Or is this a totally wrong way to go with this scenario? Thanks, Yoo

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  • How to avoid Foreign Keys constraints for all tables in DB truncate ?

    - by eugeneK
    Hi, for designing purposes i need to truncate all DB which has lots of FK's. I cannot use DELETE command simply because some tables set with Identity of TinyInts and contain about 150 items. this is a query ( truncate all tables in selected DB ) i'm trying to run Declare @t varchar (1024) Declare tbl_cur cursor for select TABLE_NAME from INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' OPEN tbl_cur FETCH NEXT from tbl_cur INTO @t WHILE @@FETCH_STATUS = 0 BEGIN EXEC ('TRUNCATE TABLE '+ @t) FETCH NEXT from tbl_cur INTO @t END CLOSE tbl_cur DEALLOCATE tbl_Cur What the best and easiest way to achieve truncate on DB with many FK's ?

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  • How to retain a row which is foreign key in another table and remove other duplicate rows?

    - by Mithril
    I have two table: A: id code 1 A1 2 A1 3 B1 4 B1 5 C1 6 C1 ===================== B: id Aid 1 1 2 4 (B doesn't contain the Aid which link to code C1) Let me explain the overall flow: I want to make each row in table A have different code(by delete duplicate),and I want to retain the Aid which I can find in table B.If Aid which not be saved in table B,I retain the id bigger one. so I can not just do something as below: DELETE FROM A WHERE id NOT IN (SELECT MAX(id) FROM A GROUP BY code, ) I can get each duplicate_code_groups by below sql statement: SELECT code FROM A GROUP BY code HAVING COUNT(*) > 1 Is there some code in sql like for (var ids in duplicate_code_groups){ for (var id in ids) { if (id in B){ return id } } return max(ids) } and put the return id into a idtable?? I just don't know how to write such code in sql. then I can do DELETE FROM A WHERE id NOT IN idtable

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  • How can I add dynamic text from a different table where primary key is a foreign key to adynamic table being shown?

    - by Jethro Tamares Doble
    I have here a dynamic table named tb_user with column region_id and institute_id and both ids are primary key of another table tb_region (with column region_name and region_id) and tb_institute (column institute_id and institute_name). I wanted to see region_name and institute_name instead of the ids. I've used this php script <?php echo $row_institute['institution_name']; ?> and query to collect data for tb_institute mysql_select_db($database_connection_ched, $connection_ched); $query_institution = "SELECT institute_id, institute_name FROM tb_institute"; $institution = mysql_query($query_institution, $connection_ched) or die(mysql_error()); $row_institution = mysql_fetch_assoc($institution); $totalRows_institution = mysql_num_rows($institution); but it seems not to display the correct name of id. query i used to collect data: mysql_select_db($database_connection_ched, $connection_ched); $query_notification = sprintf("SELECT * FROM tb_user WHERE status = 'inactive' ORDER BY date_register ASC", GetSQLValueString($colname_notification, "text")); $query_limit_notification = sprintf("%s LIMIT %d, %d", $query_notification, $startRow_notification, $maxRows_notification); $notification = mysql_query($query_limit_notification, $connection_ched) or die(mysql_error()); $row_notification = mysql_fetch_assoc($notification); if (isset($_GET['totalRows_notification'])) { $totalRows_notification = $_GET['totalRows_notification']; } else { $all_notification = mysql_query($query_notification); $totalRows_notification = mysql_num_rows($all_notification); } $totalPages_notification = ceil($totalRows_notification/$maxRows_notification)-1;

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  • mysql error #1452 appearing when trying to add a constraint

    - by user1701484
    I am trying to alter a table so That I can add a foreign key constraint in mysql database: ALTER TABLE `Question` ADD CONSTRAINT `FK_question` FOREIGN KEY (`QuestionId`) REFERENCES `Image_Question` (`QuestionId`) ON DELETE CASCADE ; Problem is that it is giving me this error: 1452 - Cannot add or update a child row: a foreign key constraint fails (mobile_app. '#sql-4517_15241', CONSTRAINT FK_question FOREIGN KEY (QuestionId) REFERENCES Image_Question (QuestionId) ON DELETE CASCADE) What does this error actually mean and what are the possible solutions I might have to undertake in order to fix this?

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  • MySql Alter Syntax error with mulitple FK

    - by acidzombie24
    If i do the first one i have no problem. When i do addition i get a syntax error. What is wrong with the syntax? The error says syntax error near [entire 2nd line] alter table `ban_Status` add FOREIGN KEY (`banned_user`) REFERENCES `user_data`(`id`) alter table `ban_Status` add FOREIGN KEY (`banned_user`) REFERENCES `user_data`(`id`), FOREIGN KEY (`banning_user`) REFERENCES `user_data`(`id`), FOREIGN KEY (`unban_user`) REFERENCES `user_data`(`id`)

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  • Solution for this SQL query?

    - by homeWorkBoy
    Suppose you have these tables: Table Name: Salesman Fields: S_ID(Primary Key), Name Table Name: Region_1 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Table Name: Region_2 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Table Name: Region_3 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Table Name: Region_4 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Query 1: Find out total of sales of each salesman in all the regions. Query 2: Find out total of sales of a particual salesman in all the regions. (if the first one is solved I think this will be easy. :-) )

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  • SQL Alter: add multiple FKs?

    - by acidzombie24
    From here ALTER TABLE ORDERS ADD FOREIGN KEY (customer_sid) REFERENCES CUSTOMER(SID); How do i add several keys with SQL Server? is it something like the below? (I cant test ATM and unfortunately i have no way to test queries unless i run it through code) ALTER TABLE ORDERS ADD FOREIGN KEY (customer_sid) REFERENCES CUSTOMER(SID), ADD FOREIGN KEY (customer_sid2) REFERENCES CUSTOMER(SID2); or is it like ALTER TABLE ORDERS ADD FOREIGN KEY (customer_sid, customer_sid2) REFERENCES CUSTOMER(SID, SID2)

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  • SQL Server script commands to check if object exists and drop it

    - by deadlydog
    Over the past couple years I’ve been keeping track of common SQL Server script commands that I use so I don’t have to constantly Google them.  Most of them are how to check if a SQL object exists before dropping it.  I thought others might find these useful to have them all in one place, so here you go: 1: --=============================== 2: -- Create a new table and add keys and constraints 3: --=============================== 4: IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = 'TableName' AND TABLE_SCHEMA='dbo') 5: BEGIN 6: CREATE TABLE [dbo].[TableName] 7: ( 8: [ColumnName1] INT NOT NULL, -- To have a field auto-increment add IDENTITY(1,1) 9: [ColumnName2] INT NULL, 10: [ColumnName3] VARCHAR(30) NOT NULL DEFAULT('') 11: ) 12: 13: -- Add the table's primary key 14: ALTER TABLE [dbo].[TableName] ADD CONSTRAINT [PK_TableName] PRIMARY KEY NONCLUSTERED 15: ( 16: [ColumnName1], 17: [ColumnName2] 18: ) 19: 20: -- Add a foreign key constraint 21: ALTER TABLE [dbo].[TableName] WITH CHECK ADD CONSTRAINT [FK_Name] FOREIGN KEY 22: ( 23: [ColumnName1], 24: [ColumnName2] 25: ) 26: REFERENCES [dbo].[Table2Name] 27: ( 28: [OtherColumnName1], 29: [OtherColumnName2] 30: ) 31: 32: -- Add indexes on columns that are often used for retrieval 33: CREATE INDEX IN_ColumnNames ON [dbo].[TableName] 34: ( 35: [ColumnName2], 36: [ColumnName3] 37: ) 38: 39: -- Add a check constraint 40: ALTER TABLE [dbo].[TableName] WITH CHECK ADD CONSTRAINT [CH_Name] CHECK (([ColumnName] >= 0.0000)) 41: END 42: 43: --=============================== 44: -- Add a new column to an existing table 45: --=============================== 46: IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS where TABLE_SCHEMA='dbo' 47: AND TABLE_NAME = 'TableName' AND COLUMN_NAME = 'ColumnName') 48: BEGIN 49: ALTER TABLE [dbo].[TableName] ADD [ColumnName] INT NOT NULL DEFAULT(0) 50: 51: -- Add a description extended property to the column to specify what its purpose is. 52: EXEC sys.sp_addextendedproperty @name=N'MS_Description', 53: @value = N'Add column comments here, describing what this column is for.' , 54: @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE', 55: @level1name = N'TableName', @level2type=N'COLUMN', 56: @level2name = N'ColumnName' 57: END 58: 59: --=============================== 60: -- Drop a table 61: --=============================== 62: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = 'TableName' AND TABLE_SCHEMA='dbo') 63: BEGIN 64: DROP TABLE [dbo].[TableName] 65: END 66: 67: --=============================== 68: -- Drop a view 69: --=============================== 70: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME = 'ViewName' AND TABLE_SCHEMA='dbo') 71: BEGIN 72: DROP VIEW [dbo].[ViewName] 73: END 74: 75: --=============================== 76: -- Drop a column 77: --=============================== 78: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS where TABLE_SCHEMA='dbo' 79: AND TABLE_NAME = 'TableName' AND COLUMN_NAME = 'ColumnName') 80: BEGIN 81: 82: -- If the column has an extended property, drop it first. 83: IF EXISTS (SELECT * FROM sys.fn_listExtendedProperty(N'MS_Description', N'SCHEMA', N'dbo', N'Table', 84: N'TableName', N'COLUMN', N'ColumnName') 85: BEGIN 86: EXEC sys.sp_dropextendedproperty @name=N'MS_Description', 87: @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE', 88: @level1name = N'TableName', @level2type=N'COLUMN', 89: @level2name = N'ColumnName' 90: END 91: 92: ALTER TABLE [dbo].[TableName] DROP COLUMN [ColumnName] 93: END 94: 95: --=============================== 96: -- Drop Primary key constraint 97: --=============================== 98: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='PRIMARY KEY' AND TABLE_SCHEMA='dbo' 99: AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'PK_Name') 100: BEGIN 101: ALTER TABLE [dbo].[TableName] DROP CONSTRAINT [PK_Name] 102: END 103: 104: --=============================== 105: -- Drop Foreign key constraint 106: --=============================== 107: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='FOREIGN KEY' AND TABLE_SCHEMA='dbo' 108: AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'FK_Name') 109: BEGIN 110: ALTER TABLE [dbo].[TableName] DROP CONSTRAINT [FK_Name] 111: END 112: 113: --=============================== 114: -- Drop Unique key constraint 115: --=============================== 116: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='UNIQUE' AND TABLE_SCHEMA='dbo' 117: AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'UNI_Name') 118: BEGIN 119: ALTER TABLE [dbo].[TableNames] DROP CONSTRAINT [UNI_Name] 120: END 121: 122: --=============================== 123: -- Drop Check constraint 124: --=============================== 125: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='CHECK' AND TABLE_SCHEMA='dbo' 126: AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'CH_Name') 127: BEGIN 128: ALTER TABLE [dbo].[TableName] DROP CONSTRAINT [CH_Name] 129: END 130: 131: --=============================== 132: -- Drop a column's Default value constraint 133: --=============================== 134: DECLARE @ConstraintName VARCHAR(100) 135: SET @ConstraintName = (SELECT TOP 1 s.name FROM sys.sysobjects s JOIN sys.syscolumns c ON s.parent_obj=c.id 136: WHERE s.xtype='d' AND c.cdefault=s.id 137: AND parent_obj = OBJECT_ID('TableName') AND c.name ='ColumnName') 138: 139: IF @ConstraintName IS NOT NULL 140: BEGIN 141: EXEC ('ALTER TABLE [dbo].[TableName] DROP CONSTRAINT ' + @ConstraintName) 142: END 143: 144: --=============================== 145: -- Example of how to drop dynamically named Unique constraint 146: --=============================== 147: DECLARE @ConstraintName VARCHAR(100) 148: SET @ConstraintName = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS 149: WHERE CONSTRAINT_TYPE='UNIQUE' AND TABLE_SCHEMA='dbo' 150: AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME LIKE 'FirstPartOfConstraintName%') 151: 152: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='UNIQUE' AND TABLE_SCHEMA='dbo' 153: AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = @ConstraintName) 154: BEGIN 155: EXEC ('ALTER TABLE [dbo].[TableName] DROP CONSTRAINT ' + @ConstraintName) 156: END 157: 158: --=============================== 159: -- Check for and drop a temp table 160: --=============================== 161: IF OBJECT_ID('tempdb..#TableName') IS NOT NULL DROP TABLE #TableName 162: 163: --=============================== 164: -- Drop a stored procedure 165: --=============================== 166: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_TYPE='PROCEDURE' AND ROUTINE_SCHEMA='dbo' AND 167: ROUTINE_NAME = 'StoredProcedureName') 168: BEGIN 169: DROP PROCEDURE [dbo].[StoredProcedureName] 170: END 171: 172: --=============================== 173: -- Drop a UDF 174: --=============================== 175: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_TYPE='FUNCTION' AND ROUTINE_SCHEMA='dbo' AND 176: ROUTINE_NAME = 'UDFName') 177: BEGIN 178: DROP FUNCTION [dbo].[UDFName] 179: END 180: 181: --=============================== 182: -- Drop an Index 183: --=============================== 184: IF EXISTS (SELECT * FROM SYS.INDEXES WHERE name = 'IndexName') 185: BEGIN 186: DROP INDEX TableName.IndexName 187: END 188: 189: --=============================== 190: -- Drop a Schema 191: --=============================== 192: IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = 'SchemaName') 193: BEGIN 194: EXEC('DROP SCHEMA SchemaName') 195: END And here’s the same code, just not in the little code view window so that you don’t have to scroll it.--=============================== -- Create a new table and add keys and constraints --=============================== IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = 'TableName' AND TABLE_SCHEMA='dbo') BEGIN CREATE TABLE [dbo].[TableName]  ( [ColumnName1] INT NOT NULL, -- To have a field auto-increment add IDENTITY(1,1) [ColumnName2] INT NULL, [ColumnName3] VARCHAR(30) NOT NULL DEFAULT('') ) -- Add the table's primary key ALTER TABLE [dbo].[TableName] ADD CONSTRAINT [PK_TableName] PRIMARY KEY NONCLUSTERED ( [ColumnName1],  [ColumnName2] ) -- Add a foreign key constraint ALTER TABLE [dbo].[TableName] WITH CHECK ADD CONSTRAINT [FK_Name] FOREIGN KEY ( [ColumnName1],  [ColumnName2] ) REFERENCES [dbo].[Table2Name]  ( [OtherColumnName1],  [OtherColumnName2] ) -- Add indexes on columns that are often used for retrieval CREATE INDEX IN_ColumnNames ON [dbo].[TableName] ( [ColumnName2], [ColumnName3] ) -- Add a check constraint ALTER TABLE [dbo].[TableName] WITH CHECK ADD CONSTRAINT [CH_Name] CHECK (([ColumnName] >= 0.0000)) END --=============================== -- Add a new column to an existing table --=============================== IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS where TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND COLUMN_NAME = 'ColumnName') BEGIN ALTER TABLE [dbo].[TableName] ADD [ColumnName] INT NOT NULL DEFAULT(0) -- Add a description extended property to the column to specify what its purpose is. EXEC sys.sp_addextendedproperty @name=N'MS_Description',  @value = N'Add column comments here, describing what this column is for.' ,  @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE', @level1name = N'TableName', @level2type=N'COLUMN', @level2name = N'ColumnName' END --=============================== -- Drop a table --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = 'TableName' AND TABLE_SCHEMA='dbo') BEGIN DROP TABLE [dbo].[TableName] END --=============================== -- Drop a view --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME = 'ViewName' AND TABLE_SCHEMA='dbo') BEGIN DROP VIEW [dbo].[ViewName] END --=============================== -- Drop a column --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS where TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND COLUMN_NAME = 'ColumnName') BEGIN -- If the column has an extended property, drop it first. IF EXISTS (SELECT * FROM sys.fn_listExtendedProperty(N'MS_Description', N'SCHEMA', N'dbo', N'Table', N'TableName', N'COLUMN', N'ColumnName') BEGIN EXEC sys.sp_dropextendedproperty @name=N'MS_Description',  @level0type=N'SCHEMA',@level0name=N'dbo', @level1type=N'TABLE', @level1name = N'TableName', @level2type=N'COLUMN', @level2name = N'ColumnName' END ALTER TABLE [dbo].[TableName] DROP COLUMN [ColumnName] END --=============================== -- Drop Primary key constraint --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='PRIMARY KEY' AND TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'PK_Name') BEGIN ALTER TABLE [dbo].[TableName] DROP CONSTRAINT [PK_Name] END --=============================== -- Drop Foreign key constraint --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='FOREIGN KEY' AND TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'FK_Name') BEGIN ALTER TABLE [dbo].[TableName] DROP CONSTRAINT [FK_Name] END --=============================== -- Drop Unique key constraint --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='UNIQUE' AND TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'UNI_Name') BEGIN ALTER TABLE [dbo].[TableNames] DROP CONSTRAINT [UNI_Name] END --=============================== -- Drop Check constraint --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='CHECK' AND TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = 'CH_Name') BEGIN ALTER TABLE [dbo].[TableName] DROP CONSTRAINT [CH_Name] END --=============================== -- Drop a column's Default value constraint --=============================== DECLARE @ConstraintName VARCHAR(100) SET @ConstraintName = (SELECT TOP 1 s.name FROM sys.sysobjects s JOIN sys.syscolumns c ON s.parent_obj=c.id WHERE s.xtype='d' AND c.cdefault=s.id  AND parent_obj = OBJECT_ID('TableName') AND c.name ='ColumnName') IF @ConstraintName IS NOT NULL BEGIN EXEC ('ALTER TABLE [dbo].[TableName] DROP CONSTRAINT ' + @ConstraintName) END --=============================== -- Example of how to drop dynamically named Unique constraint --=============================== DECLARE @ConstraintName VARCHAR(100) SET @ConstraintName = (SELECT TOP 1 CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS  WHERE CONSTRAINT_TYPE='UNIQUE' AND TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME LIKE 'FirstPartOfConstraintName%') IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE='UNIQUE' AND TABLE_SCHEMA='dbo' AND TABLE_NAME = 'TableName' AND CONSTRAINT_NAME = @ConstraintName) BEGIN EXEC ('ALTER TABLE [dbo].[TableName] DROP CONSTRAINT ' + @ConstraintName) END --=============================== -- Check for and drop a temp table --=============================== IF OBJECT_ID('tempdb..#TableName') IS NOT NULL DROP TABLE #TableName --=============================== -- Drop a stored procedure --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_TYPE='PROCEDURE' AND ROUTINE_SCHEMA='dbo' AND ROUTINE_NAME = 'StoredProcedureName') BEGIN DROP PROCEDURE [dbo].[StoredProcedureName] END --=============================== -- Drop a UDF --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_TYPE='FUNCTION' AND ROUTINE_SCHEMA='dbo' AND  ROUTINE_NAME = 'UDFName') BEGIN DROP FUNCTION [dbo].[UDFName] END --=============================== -- Drop an Index --=============================== IF EXISTS (SELECT * FROM SYS.INDEXES WHERE name = 'IndexName') BEGIN DROP INDEX TableName.IndexName END --=============================== -- Drop a Schema --=============================== IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = 'SchemaName') BEGIN EXEC('DROP SCHEMA SchemaName') END

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  • One to two relationship in Doctrine with YAML

    - by Jeremy DeGroot
    I'm working on my first Symfony project with Doctrine, and I've run into a hitch. I'm trying to express a game with two players. The relationship I want to have is PlayerOne and PlayerTwo each being keyed to an ID in the Users table. This is part of what I've got so far: Game: actAs: { Timestampable:- } columns: id: { type: integer, notnull: true, unique: true } startDate: { type: timestamp, notnull: true } playerOne: { type: integer, notnull: true } playerTwo: { type: integer, notnull: true } winner: { type: integer, notnull:true, default:0 } relations: User: { onUpdate: cascade, local: playerOne, foreign: id} User: { onUpdate: cascade, local: playerTwo, foreign: id} That doesn't work. It builds fine, but the SQL it generates only includes a constraint for playerTwo. I've tried a few other things: User: { onUpdate: cascade, local: [playerOne, playerTwo], foreign: id} Also: User: [{ onUpdate: cascade, local: playerOne, foreign: id}, { onUpdate: cascade, local: playerTwo, foreign: id}] Those last two throw errors when I try to build. Is there anyone out there who understands what I'm trying to do and can help me achieve it?

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  • Complex Query on cassandra

    - by Sadiqur Rahman
    I have heard on cassandra database engine few days ago and searching for a good documentation on it. after studying on cassandra I got cassandra is more scalable than other data engine. I also read on Amazon SimpleDB but as SimpleDB has a limitation 10GB/table and Google Datastore is slower than Amazon SimpleDB, I prefer not to use them (Google Datastore, Amazon SimpleDB). So for making our site scaled specially high write rates with massive data, I like to use Cassandra as our Data Engine. But before starting using cassandra I am confused on "How to handle complex data using casssandra". I am giving you the MySQL database structure below, Please read this and give me a good suggestion. Users Table hasColum ID Primary hasColum email Unique hasColum FirstName hasColum LastName Category Table hasColum ID Primary hasColum Parent hasColum Category Posts Table hasColum ID Primary hasColum UID Index foreign key linked to users-ID hasColum CID Index foreign key linked to Category-ID hasColum Title hasColum Post Index hasColum PunDate Comments hasColum ID primary hasColum UID Index foreign key linked to users-ID hasColum PID Index foreign key linked to Posts-ID hasColum Comment User Group hasColum ID primary hasColum Name UserToGroup Table (for many to many relation only) hasColum UID foreign key linked to Users-ID hasColum GID foreign key linked to Group-ID Finally for your information, I like to use SimpleCassie PHP Class http://code.google.com/p/simpletools-php/ So, it will be very helpful if you can give me example using SimpleCassie

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  • Association Mapping Details confusion?

    - by AaronLS
    I have never understood why the associations in EntityFramework look the way they do in the Mapping Details window. When I select the line between 2 tables for an association, for example FK_ApplicationSectionsNodes_FormItems, it shows this: Association Maps to ApplicationSectionNodes FormItems (key symbol) FormItemId:Int32 <--> FormItemId:int ApplicationSectionNodes (key symbol) NodeId:Int32 <--> (key symbol) NodeId : int Fortunately this one was create automatically for me based on the foreign key constraints in my database, but whenever no constraints exist, I have a hard to creating associations manually(when the database doesn't have a diagram setup) because I don't understand the mapping details for associations. FormItems table has a primary key identity column FormItemId, and ApplicationSectionNodes contains a FormItemId column that is the foreign key and has NodeId as a primary key identity column. What really makes no sense to me is why the association has anything listed about the NodeId, when NodeId doesn't have anything to do with the foreign key relationship? (It's even more confusing with self referencing relationships, but maybe if I could understand the above case I'd have a better handle). CREATE TABLE [dbo].[ApplicationSectionNodes]( [NodeID] [int] IDENTITY(1,1) NOT NULL, [OutlineText] [varchar](5000) NULL, [ParentNodeID] [int] NULL, [FormItemId] [int] NULL, CONSTRAINT [PK_ApplicationSectionNodes] PRIMARY KEY CLUSTERED ( [NodeID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY], CONSTRAINT [UQ_ApplicationSectionNodesFormItemId] UNIQUE NONCLUSTERED ( [FormItemId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[ApplicationSectionNodes] WITH NOCHECK ADD CONSTRAINT [FK_ApplicationSectionNodes_ApplicationSectionNodes] FOREIGN KEY([ParentNodeID]) REFERENCES [dbo].[ApplicationSectionNodes] ([NodeID]) GO ALTER TABLE [dbo].[ApplicationSectionNodes] NOCHECK CONSTRAINT [FK_ApplicationSectionNodes_ApplicationSectionNodes] GO ALTER TABLE [dbo].[ApplicationSectionNodes] WITH NOCHECK ADD CONSTRAINT [FK_ApplicationSectionNodes_FormItems] FOREIGN KEY([FormItemId]) REFERENCES [dbo].[FormItems] ([FormItemId]) GO ALTER TABLE [dbo].[ApplicationSectionNodes] NOCHECK CONSTRAINT [FK_ApplicationSectionNodes_FormItems] GO FormItems Table: CREATE TABLE [dbo].[FormItems]( [FormItemId] [int] IDENTITY(1,1) NOT NULL, [FormItemType] [int] NULL, CONSTRAINT [PK_FormItems] PRIMARY KEY CLUSTERED ( [FormItemId] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[FormItems] WITH NOCHECK ADD CONSTRAINT [FK_FormItems_FormItemTypes] FOREIGN KEY([FormItemType]) REFERENCES [dbo].[FormItemTypes] ([FormItemTypeId]) GO ALTER TABLE [dbo].[FormItems] NOCHECK CONSTRAINT [FK_FormItems_FormItemTypes] GO

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  • Complex Quary on cassandra

    - by Sadiqur Rahman
    I have heard on cassandra database engine few days ago and searching for a good documentation on it. after studying on cassandra I got cassandra is more scalable than other data engine. I also read on Amazon SimpleDB but as SimpleDB has a limitation 10GB/table and Google Datastore is slower than Amazon SimpleDB, I prefer not to use them (Google Datastore, Amazon SimpleDB). So for making our site scaled specially high write rates with massive data, I like to use Cassandra as out Data Engine. But before starting using cassandra I am confused on "How to handle complex data using casssandra". I am giving you the MySQL database structure below, Please read this and give me a good suggestion. Users Table hasColum ID Primary hasColum email Unique hasColum FirstName hasColum LastName Category Table hasColum ID Primary hasColum Parent hasColum Category Posts Table hasColum ID Primary hasColum UID Index foreign key linked to users-ID hasColum CID Index foreign key linked to Category-ID hasColum Title hasColum Post Index hasColum PunDate Comments hasColum ID primary hasColum UID Index foreign key linked to users-ID hasColum PID Index foreign key linked to Posts-ID hasColum Comment User Group hasColum ID primary hasColum Name UserToGroup Table (for many to many relation only) hasColum UID foreign key linked to Users-ID hasColum GID foreign key linked to Group-ID Finally for your information, I like to use SimpleCassie PHP Class http://code.google.com/p/simpletools-php/ So, it will be very helpful if you can give me example using SimpleCassie

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  • LLBLGen Pro feature highlights: automatic element name construction

    - by FransBouma
    (This post is part of a series of posts about features of the LLBLGen Pro system) One of the things one might take for granted but which has a huge impact on the time spent in an entity modeling environment is the way the system creates names for elements out of the information provided, in short: automatic element name construction. Element names are created in both directions of modeling: database first and model first and the more names the system can create for you without you having to rename them, the better. LLBLGen Pro has a rich, fine grained system for creating element names out of the meta-data available, which I'll describe more in detail below. First the model element related element naming features are highlighted, in the section Automatic model element naming features and after that I'll go more into detail about the relational model element naming features LLBLGen Pro has to offer in the section Automatic relational model element naming features. Automatic model element naming features When working database first, the element names in the model, e.g. entity names, entity field names and so on, are in general determined from the relational model element (e.g. table, table field) they're mapped on, as the model elements are reverse engineered from these relational model elements. It doesn't take rocket science to automatically name an entity Customer if the entity was created after reverse engineering a table named Customer. It gets a little trickier when the entity which was created by reverse engineering a table called TBL_ORDER_LINES has to be named 'OrderLine' automatically. Automatic model element naming also takes into effect with model first development, where some settings are used to provide you with a default name, e.g. in the case of navigator name creation when you create a new relationship. The features below are available to you in the Project Settings. Open Project Settings on a loaded project and navigate to Conventions -> Element Name Construction. Strippers! The above example 'TBL_ORDER_LINES' shows that some parts of the table name might not be needed for name creation, in this case the 'TBL_' prefix. Some 'brilliant' DBAs even add suffixes to table names, fragments you might not want to appear in the entity names. LLBLGen Pro offers you to define both prefix and suffix fragments to strip off of table, view, stored procedure, parameter, table field and view field names. In the example above, the fragment 'TBL_' is a good candidate for such a strip pattern. You can specify more than one pattern for e.g. the table prefix strip pattern, so even a really messy schema can still be used to produce clean names. Underscores Be Gone Another thing you might get rid of are underscores. After all, most naming schemes for entities and their classes use PasCal casing rules and don't allow for underscores to appear. LLBLGen Pro can automatically strip out underscores for you. It's an optional feature, so if you like the underscores, you're not forced to see them go: LLBLGen Pro will leave them alone when ordered to to so. PasCal everywhere... or not, your call LLBLGen Pro can automatically PasCal case names on word breaks. It determines word breaks in a couple of ways: a space marks a word break, an underscore marks a word break and a case difference marks a word break. It will remove spaces in all cases, and based on the underscore removal setting, keep or remove the underscores, and upper-case the first character of a word break fragment, and lower case the rest. Say, we keep the defaults, which is remove underscores and PasCal case always and strip the TBL_ fragment, we get with our example TBL_ORDER_LINES, after stripping TBL_ from the table name two word fragments: ORDER and LINES. The underscores are removed, the first character of each fragment is upper-cased, the rest lower-cased, so this results in OrderLines. Almost there! Pluralization and Singularization In general entity names are singular, like Customer or OrderLine so LLBLGen Pro offers a way to singularize the names. This will convert OrderLines, the result we got after the PasCal casing functionality, into OrderLine, exactly what we're after. Show me the patterns! There are other situations in which you want more flexibility. Say, you have an entity Customer and an entity Order and there's a foreign key constraint defined from the target of Order and the target of Customer. This foreign key constraint results in a 1:n relationship between the entities Customer and Order. A relationship has navigators mapped onto the relationship in both entities the relationship is between. For this particular relationship we'd like to have Customer as navigator in Order and Orders as navigator in Customer, so the relationship becomes Customer.Orders 1:n Order.Customer. To control the naming of these navigators for the various relationship types, LLBLGen Pro defines a set of patterns which allow you, using macros, to define how the auto-created navigator names will look like. For example, if you rather have Customer.OrderCollection, you can do so, by changing the pattern from {$EndEntityName$P} to {$EndEntityName}Collection. The $P directive makes sure the name is pluralized, which is not what you want if you're going for <EntityName>Collection, hence it's removed. When working model first, it's a given you'll create foreign key fields along the way when you define relationships. For example, you've defined two entities: Customer and Order, and they have their fields setup properly. Now you want to define a relationship between them. This will automatically create a foreign key field in the Order entity, which reflects the value of the PK field in Customer. (No worries if you hate the foreign key fields in your classes, on NHibernate and EF these can be hidden in the generated code if you want to). A specific pattern is available for you to direct LLBLGen Pro how to name this foreign key field. For example, if all your entities have Id as PK field, you might want to have a different name than Id as foreign key field. In our Customer - Order example, you might want to have CustomerId instead as foreign key name in Order. The pattern for foreign key fields gives you that freedom. Abbreviations... make sense of OrdNr and friends I already described word breaks in the PasCal casing paragraph, how they're used for the PasCal casing in the constructed name. Word breaks are used for another neat feature LLBLGen Pro has to offer: abbreviation support. Burt, your friendly DBA in the dungeons below the office has a hate-hate relationship with his keyboard: he can't stand it: typing is something he avoids like the plague. This has resulted in tables and fields which have names which are very short, but also very unreadable. Example: our TBL_ORDER_LINES example has a lovely field called ORD_NR. What you would like to see in your fancy new OrderLine entity mapped onto this table is a field called OrderNumber, not a field called OrdNr. What you also like is to not have to rename that field manually. There are better things to do with your time, after all. LLBLGen Pro has you covered. All it takes is to define some abbreviation - full word pairs and during reverse engineering model elements from tables/views, LLBLGen Pro will take care of the rest. For the ORD_NR field, you need two values: ORD as abbreviation and Order as full word, and NR as abbreviation and Number as full word. LLBLGen Pro will now convert every word fragment found with the word breaks which matches an abbreviation to the given full word. They're case sensitive and can be found in the Project Settings: Navigate to Conventions -> Element Name Construction -> Abbreviations. Automatic relational model element naming features Not everyone works database first: it may very well be the case you start from scratch, or have to add additional tables to an existing database. For these situations, it's key you have the flexibility that you can control the created table names and table fields without any work: let the designer create these names based on the entity model you defined and a set of rules. LLBLGen Pro offers several features in this area, which are described in more detail below. These features are found in Project Settings: navigate to Conventions -> Model First Development. Underscores, welcome back! Not every database is case insensitive, and not every organization requires PasCal cased table/field names, some demand all lower or all uppercase names with underscores at word breaks. Say you create an entity model with an entity called OrderLine. You work with Oracle and your organization requires underscores at word breaks: a table created from OrderLine should be called ORDER_LINE. LLBLGen Pro allows you to do that: with a simple checkbox you can order LLBLGen Pro to insert an underscore at each word break for the type of database you're working with: case sensitive or case insensitive. Checking the checkbox Insert underscore at word break case insensitive dbs will let LLBLGen Pro create a table from the entity called Order_Line. Half-way there, as there are still lower case characters there and you need all caps. No worries, see below Casing directives so everyone can sleep well at night For case sensitive databases and case insensitive databases there is one setting for each of them which controls the casing of the name created from a model element (e.g. a table created from an entity definition using the auto-mapping feature). The settings can have the following values: AsProjectElement, AllUpperCase or AllLowerCase. AsProjectElement is the default, and it keeps the casing as-is. In our example, we need to get all upper case characters, so we select AllUpperCase for the setting for case sensitive databases. This will produce the name ORDER_LINE. Sequence naming after a pattern Some databases support sequences, and using model-first development it's key to have sequences, when needed, to be created automatically and if possible using a name which shows where they're used. Say you have an entity Order and you want to have the PK values be created by the database using a sequence. The database you're using supports sequences (e.g. Oracle) and as you want all numeric PK fields to be sequenced, you have enabled this by the setting Auto assign sequences to integer pks. When you're using LLBLGen Pro's auto-map feature, to create new tables and constraints from the model, it will create a new table, ORDER, based on your settings I previously discussed above, with a PK field ID and it also creates a sequence, SEQ_ORDER, which is auto-assigns to the ID field mapping. The name of the sequence is created by using a pattern, defined in the Model First Development setting Sequence pattern, which uses plain text and macros like with the other patterns previously discussed. Grouping and schemas When you start from scratch, and you're working model first, the tables created by LLBLGen Pro will be in a catalog and / or schema created by LLBLGen Pro as well. If you use LLBLGen Pro's grouping feature, which allows you to group entities and other model elements into groups in the project (described in a future blog post), you might want to have that group name reflected in the schema name the targets of the model elements are in. Say you have a model with a group CRM and a group HRM, both with entities unique for these groups, e.g. Employee in HRM, Customer in CRM. When auto-mapping this model to create tables, you might want to have the table created for Employee in the HRM schema but the table created for Customer in the CRM schema. LLBLGen Pro will do just that when you check the setting Set schema name after group name to true (default). This gives you total control over where what is placed in the database from your model. But I want plural table names... and TBL_ prefixes! For now we follow best practices which suggest singular table names and no prefixes/suffixes for names. Of course that won't keep everyone happy, so we're looking into making it possible to have that in a future version. Conclusion LLBLGen Pro offers a variety of options to let the modeling system do as much work for you as possible. Hopefully you enjoyed this little highlight post and that it has given you new insights in the smaller features available to you in LLBLGen Pro, ones you might not have thought off in the first place. Enjoy!

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  • Why does Perl lose foreign characters on Windows input - can this be fixed (if so, how) or is Perl an outdated dinosaur that just can't handle this?

    - by Alex R
    Note below how ã changes to a This is causing me a huge problem as foreign characters show up in URLs, e.g. http://pt.wikipedia.org/wiki/Cão The OS is Windows 7, 64-bit. The Perl is: This is perl 5, version 12, subversion 2 (v5.12.2) built for MSWin32-x64-multi-thread (with 8 registered patches, see perl -V for more detail) Copyright 1987-2010, Larry Wall Binary build 1202 [293621] provided by ActiveState http://www.ActiveState.com Built Sep 6 2010 22:53:42 Additional update: To get around my particular problem, I tried using File::Find instead of piped input. The issue actually gets worse:

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  • Deleting a row from self-referencing table

    - by Jake Rutherford
    Came across this the other day and thought “this would be a great interview question!” I’d created a table with a self-referencing foreign key. The application was calling a stored procedure I’d created to delete a row which caused but of course…a foreign key exception. You may say “why not just use a the cascade delete option?” Good question, easy answer. With a typical foreign key relationship between different tables which would work. However, even SQL Server cannot do a cascade delete of a row on a table with self-referencing foreign key. So, what do you do?…… In my case I re-wrote the stored procedure to take advantage of recursion:   -- recursively deletes a Foo ALTER PROCEDURE [dbo].[usp_DeleteFoo]      @ID int     ,@Debug bit = 0    AS     SET NOCOUNT ON;     BEGIN TRANSACTION     BEGIN TRY         DECLARE @ChildFoos TABLE         (             ID int         )                 DECLARE @ChildFooID int                        INSERT INTO @ChildFoos         SELECT ID FROM Foo WHERE ParentFooID = @ID                 WHILE EXISTS (SELECT ID FROM @ChildFoos)         BEGIN             SELECT TOP 1                 @ChildFooID = ID             FROM                 @ChildFoos                             DELETE FROM @ChildFoos WHERE ID = @ChildFooID                         EXEC usp_DeleteFoo @ChildFooID         END                                    DELETE FROM dbo.[Foo]         WHERE [ID] = @ID                 IF @Debug = 1 PRINT 'DEBUG:usp_DeleteFoo, deleted - ID: ' + CONVERT(VARCHAR, @ID)         COMMIT TRANSACTION     END TRY     BEGIN CATCH         ROLLBACK TRANSACTION         DECLARE @ErrorMessage VARCHAR(4000), @ErrorSeverity INT, @ErrorState INT         SELECT @ErrorMessage = ERROR_MESSAGE(), @ErrorSeverity = ERROR_SEVERITY(), @ErrorState = ERROR_STATE()         IF @ErrorState <= 0 SET @ErrorState = 1         INSERT INTO ErrorLog(ErrorNumber,ErrorSeverity,ErrorState,ErrorProcedure,ErrorLine,ErrorMessage)         VALUES(ERROR_NUMBER(), @ErrorSeverity, @ErrorState, ERROR_PROCEDURE(), ERROR_LINE(), @ErrorMessage)         RAISERROR (@ErrorMessage, @ErrorSeverity, @ErrorState)     END CATCH   This procedure will first determine any rows which have the row we wish to delete as it’s parent. It then simply iterates each child row calling the procedure recursively in order to delete all ancestors before eventually deleting the row we wish to delete.

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