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How do you use variables in a simple PostgreSQL script?
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Here's an example of using a variable in plpgsql:
create table test (id int);
insert into test values (1);
insert into test values (2);
insert into test values (3);
create function test_fn() returns int as $$
declare val int := 2;
begin
return (SELECT id FROM test ...
SQL query to group by day
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If you're using SQL Server, you could add three calculated fields to your table:
Sales (saleID INT, amount INT, created DATETIME)
ALTER TABLE dbo.Sales
ADD SaleYear AS YEAR(Created) PERSISTED
ALTER TABLE dbo.Sales
ADD SaleMonth AS MONTH(Created) PERSISTED
ALTER TABLE dbo.Sales
ADD SaleDay A...
UITableView row animation duration and completion callback
Is there a way to either specify the duration for UITableView row animations, or to get a callback when the animation completes?
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How to think in data stores instead of databases?
...trained my mind to think 100% in object relationships that map directly to table structures, and now it's hard to see anything differently. I can understand some of the benefits of Google Datastore (e.g. performance and the ability to distribute data), but some good database functionality is sacrif...
MySQL “Group By” and “Order By”
I want to be able to select a bunch of rows from a table of e-mails and group them by the from sender. My query looks like this:
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SQL join: selecting the last records in a one-to-many relationship
Suppose I have a table of customers and a table of purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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How to place div side by side
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Using CSS display property - which can be used to make divs act like a table:
<div style="width: 100%; display: table;">
<div style="display: table-row">
<div style="width: 600px; display: table-cell;"> Left </div>
<div style="display: table-ce...
Stored procedure slow when called from web, fast from Management Studio
... change:
ALTER PROCEDURE [dbo].[sproc]
@param1 int,
AS
SELECT * FROM Table WHERE ID = @param1
to:
ALTER PROCEDURE [dbo].[sproc]
@param1 int,
AS
DECLARE @param1a int
SET @param1a = @param1
SELECT * FROM Table WHERE ID = @param1a
Seems strange, but it fixed my problem.
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How to load a tsv file into a Pandas DataFrame?
...od - it was very slow and failed indexing at the end. Instead, i used read_table(), which worked much faster and without the extra param.
– Yurik
Aug 15 '14 at 9:56
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SQL Server Text type vs. varchar data type [closed]
...NTEXT. You'll need to enable large value types out of row for them with sp_tableoption if you want them to be always stored out of row.
As mentioned above and here, TEXT is going to be deprecated in future releases:
The text in row option will be removed in a future version of SQL Server. Avoid usi...