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Using Excel OleDb to get sheet names IN SHEET ORDER
...tring excelFile)
{
OleDbConnection objConn = null;
System.Data.DataTable dt = null;
try
{
// Connection String. Change the excel file to the file you
// will search.
String connString = "Provider=Microsoft.Jet.OLEDB.4.0;" +
"Data Source=" + excelFi...
Create code first, many to many, with additional fields in association table
... not possible to create a many-to-many relationship with a customized join table. In a many-to-many relationship EF manages the join table internally and hidden. It's a table without an Entity class in your model. To work with such a join table with additional properties you will have to create actu...
Many-to-many relationship with the same model in rails?
...dditional information with the association? (Additional fields in the join table.)
Do the associations need to be implicitly bi-directional?
(If post A is connected to post B, then post B is also connected to post A.)
That leaves four different possibilities. I'll walk over these below.
For refer...
How to create a unique index on a NULL column?
...
create unique index UIX on MyTable (Column1) where Column1 is not null
– Jørn Schou-Rode
Dec 2 '10 at 14:54
1
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Find most frequent value in SQL column
How can I find the most frequent value in a given column in an SQL table?
9 Answers
9
...
An explicit value for the identity column in table can only be specified when a column list is used
...e identity column in tbl_A_archive a regular, non-identity column: If your table is an archive table and you always specify an explicit value for the identity column, why do you even need an identity column? Just use a regular int instead.
Details on Solution 1
Instead of
SET IDENTITY_INSERT archi...
Cannot insert explicit value for identity column in table 'table' when IDENTITY_INSERT is set to OFF
...tionId that is an identity column.
You can turn on identity insert on the table like this so that you can specify your own identity values.
SET IDENTITY_INSERT Table1 ON
INSERT INTO Table1
/*Note the column list is REQUIRED here, not optional*/
(OperationID,
OpDescription...
Primary key or Unique index?
...e two equal values in that column in two different rows. Example:
CREATE TABLE table1 (foo int, bar int);
CREATE UNIQUE INDEX ux_table1_foo ON table1(foo); -- Create unique index on foo.
INSERT INTO table1 (foo, bar) VALUES (1, 2); -- OK
INSERT INTO table1 (foo, bar) VALUES (2, 2); -- OK
INSERT ...
How can I get column names from a table in SQL Server?
I want to query the name of all columns of a table. I found how to do this in:
20 Answers
...
Is C++14 adding new keywords to C++?
...
Table 4 (Keywords) in N3936 (C++14):
alignas continue friend register true
alignof decltype goto reinterpret_cast try
asm default ...