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Reset auto increment counter in postgres
I would like to force the auto increment field of a table to some value, I tried with this:
12 Answers
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Oracle: how to UPSERT (update or insert into a table?)
The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data:
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How to add multiple columns to a table in Postgres?
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Try this :
ALTER TABLE table ADD COLUMN col1 int, ADD COLUMN col2 int;
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MySQL maximum memory usage
...the (f'ing) manual.
As for the database -- a few important constraints:
table engine (InnoDB, MyISAM, ...)
size
indices
usage
Most MySQL tips on stackoverflow will tell you about 5-8 so called important settings. First off, not all of them matter - e.g. allocating a lot of resources to InnoDB a...
Is there a better way to dynamically build an SQL WHERE clause than by using 1=1 at its beginning?
... offer you:
using (var dbContext = new MyDbContext())
{
IQueryable<Table1Item> query = dbContext.Table1;
if (condition1)
{
query = query.Where(c => c.Col1 == 0);
}
if (condition2)
{
query = query.Where(c => c.Col2 == 1);
}
if (condition3)...
Can we pass parameters to a view in SQL?
...t a stored function, like:
CREATE FUNCTION v_emp (@pintEno INT)
RETURNS TABLE
AS
RETURN
SELECT * FROM emp WHERE emp_id=@pintEno;
This allows you to use it as a normal view, with:
SELECT * FROM v_emp(10)
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Ship an application with a database
...re database from there. This is much quicker if the database has a lot of tables and other components. Upgrades are triggered by changing the database version number in the res/values/strings.xml file. Upgrades would then be accomplished by creating a new database externally, replacing the old dat...
MySQL - Make an existing Field Unique
I have an already existing table with a field that should be unique but is not. I only know this because an entry was made into the table that had the same value as another, already existing, entry and this caused problems.
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HTML table headers always visible at top of window when viewing a large table
I would like to be able to "tweak" an HTML table's presentation to add a single feature: when scrolling down through the page so that the table is on the screen but the header rows are off-screen, I would like the headers to remain visible at the top of the viewing area.
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Foreign key constraints: When to use ON UPDATE and ON DELETE
...eign key constraints are quite advanced.
We'll take an example, a company table with a user table containing people from theses company
CREATE TABLE COMPANY (
company_id INT NOT NULL,
company_name VARCHAR(50),
PRIMARY KEY (company_id)
) ENGINE=INNODB;
CREATE TABLE USER (
user_...