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Add border-bottom to table row
I have a table of 3 by 3. I need a way to add a border for the bottom of every row tr and give it a specific color.
16 An...
SQL Server insert if not exists best practice
I have a Competitions results table which holds team member's names and their ranking on one hand.
8 Answers
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How do I UPDATE from a SELECT in SQL Server?
In SQL Server , it is possible to insert rows into a table with an INSERT.. SELECT statement:
35 Answers
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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...
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 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;
+---...
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...
How to take backup of a single table in a MySQL database?
...sqldump takes the backup of an entire database. I need to backup a single table in MySQL. Is it possible? How do I restore it?
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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?
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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...