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Multiple “order by” in LINQ
I have two tables, movies and categories , and I get an ordered list by categoryID first and then by Name .
7 Answers...
How to update column with null value
...
No special syntax:
CREATE TABLE your_table (some_id int, your_column varchar(100));
INSERT INTO your_table VALUES (1, 'Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---...
Does MySQL ignore null values on unique constraints?
... MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL...
Get the new record primary key ID from MySQL insert query?
Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
...
In a bootstrap responsive page how to center a div
...http://getbootstrap.com/dist/css/bootstrap.css');
html, body, .container-table {
height: 100%;
}
.container-table {
display: table;
}
.vertical-center-row {
display: table-cell;
vertical-align: middle;
}
<script src="http://cdnjs.cloudflare.com/ajax/libs/twitter-bootst...
How do I safely pass objects, especially STL objects, to and from a DLL?
...a plain C interface using extern "C", since the C ABI is well-defined and stable.
If you really, really want to pass C++ objects across a DLL boundary, it's technically possible. Here are some of the factors you'll have to account for:
Data packing/alignment
Within a given class, individual dat...
Rename column SQL Server 2008
I am using SQL Server 2008 and Navicat. I need to rename a column in a table using SQL.
11 Answers
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Postgres dump of only parts of tables for a dev snapshot
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On your larger tables you can use the COPY command to pull out subsets...
COPY (SELECT * FROM mytable WHERE ...) TO '/tmp/myfile.tsv'
COPY mytable FROM 'myfile.tsv'
https://www.postgresql.org/docs/current/static/sql-copy.html
You shoul...
Using an RDBMS as event sourcing storage
...1 and 2 at all.
Below is the schema as used in Ncqrs. As you can see, the table "Events" stores the related data as a CLOB (i.e. JSON or XML). This corresponds to your option 3 (Only that there is no "ProductEvents" table because you only need one generic "Events" table. In Ncqrs the mapping to you...
Clustered vs Non-Clustered
... PersonId means that the rows will be physically sorted by PersonId in the table, allowing an index search on this to go straight to the row (rather than a non-clustered index, which would direct you to the row's location, adding an extra step).
That said, it's unusual for the primary key not to be...