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Knight's Shortest Path on Chessboard
...tance(x,y)+'</td>';
}
html += '</tr>';
}
html = '<table>'+html+'</table>';
$body.append(html);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
Note: The jQuery used for only illustration, for code see dis...
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...
Safe characters for friendly url [closed]
...Or in other words: You may use any (non-control-) character from the ASCII table, except /, ?, #, [ and ].
This understanding is backed by RFC1738 - Uniform Resource Locators (URL).
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How to find all the tables in MySQL with specific column names in them?
...rent column names that I want to look up in the entire DB and list out all tables which have those columns. Any easy script?
...
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;
+---...
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...
Postgres dump of only parts of tables for a dev snapshot
...
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...
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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Modify table: How to change 'Allow Nulls' attribute from not null to allow null
How to change one attribute in a table using T-SQL to allow nulls (not null --> null)? Alter table maybe?
8 Answers
...
How can I use PowerShell with the Visual Studio Command Prompt?
...output of cmd.exe. We also ask cmd.exe to output
## the environment table after the batch file completes
cmd.exe /c " `"$Path`" $Parameters && set > `"$tempFile`" "
## Go through the environment variables in the temp file.
## For each of them, set the variable in our...