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What can I do to resolve a “Row not found or changed” Exception in LINQ to SQL on a SQL Server Compa
... types for all fields in the O/R-Designer match the data types in your SQL table.
Double check for nullable! A column should be either nullable in both the O/R-Designer and SQL, or not nullable in both.
For example, a NVARCHAR column "title" is marked as NULLable in your database, and contains the ...
How to create a unique index on a NULL column?
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create unique index UIX on MyTable (Column1) where Column1 is not null
– Jørn Schou-Rode
Dec 2 '10 at 14:54
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Postgres manually alter sequence
... ALTER SEQUENCE [sequence] RESTART WITH (SELECT MAX(col) from table); does not work, whereas SELECT setval('sequence', (SELECT (MAX(col) from table), TRUE); does work. I get a syntax error. (Postgres 9.4)
– NuclearPeon
Jul 21 '18 at 1:35
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What's the fastest way to do a bulk insert into Postgres?
...e as CSV formatted mapping in PG query statement's. You can try for Big Table?
– Elyor
Sep 9 '14 at 2:03
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A migration to add unique constraint to a combination of columns
...o apply unique constraint to a combination of columns. i.e. for a people table, a combination of first_name , last_Name and Dob should be unique.
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Checking if a SQL Server login already exists
...ction. Attacker can pass a @loginName like x] with password ''y'';\r\ndrop table foo;\r\n
– Remus Rusanu
Sep 4 '09 at 14:47
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How to efficiently build a tree from a flat structure?
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Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all the objects and find their parent if it exists and update its parent pointer accordingly.
class MyObject
{ // The actual object
public int ParentID { get; set; ...
NHibernate vs LINQ to SQL
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LINQ to SQL forces you to use the table-per-class pattern. The benefits of using this pattern are that it's quick and easy to implement and it takes very little effort to get your domain running based on an existing database structure. For simple applicatio...
NULL values inside NOT IN clause
...s one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the concept.
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read.csv warning 'EOF within quoted string' prevents complete reading of file
...ng 403 back with read.csv(). Adding quote = "" got me up to 410 rows. read.table() does no better. I wonder what else can be tried...
– Hack-R
Aug 21 '14 at 15:12
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