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Add a column to existing table and uniquely number them on MS SQL Server
...the database but for SQL Server, this could be achieved as follows:
alter table Example
add NewColumn int identity(1,1)
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Cast Int to enum in Java
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@Tarrasch as arrays are mutable, values() must return a copy of the array of elements just in case you happen to change it. Creating this copy each time is relatively expensive.
– Peter Lawrey
Dec 4 '12 at 8:44
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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...
How to update column with null value
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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;
+---...
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...
jQuery DataTables: control table width
I have a problem controlling the width of a table using the jQuery DataTables plugin. The table is supposed to be 100% of the container width, but ends up being an arbitrary width, rather less than the container width.
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INSERT with SELECT
...unning select next time? if I want to insert and get the result of courses table
– TAHA SULTAN TEMURI
Oct 8 '19 at 13:05
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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...
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 .
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How to create a backup of a single table in a postgres database?
Is there a way to create a backup of a single table within a database using postgres? And how? Does this also work with the pg_dump command?
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