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How can I modify the size of column in a MySQL table?
I have created a table and accidentally put varchar length as 300 instead of 65353 . How can I fix that?
2 Answers
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Computed / calculated / virtual / derived columns in PostgreSQL
...enerated columns are introduced with Postgres 12. Trivial example:
CREATE TABLE tbl (
int1 int
, int2 int
, product bigint GENERATED ALWAYS AS (int1 * int2) STORED
);
db<>fiddle here
VIRTUAL generated columns may come with one of the next iterations. (Not in Postgres 13, yet) .
...
How do I handle too long index names in a Ruby on Rails ActiveRecord migration?
...an unique index that gets created from the foreign keys of four associated tables:
9 Answers
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How do I migrate a model out of one django app and into a new one?
...rd code
#to use just one sentence:
def forwards(self, orm):
db.rename_table('common_cat', 'specific_cat')
if not db.dry_run:
# For permissions to work properly after migrating
orm['contenttypes.contenttype'].objects.filter(
app_label='common',
model...
How to create a DataTable in C# and how to add rows?
How do create a DataTable in C#?
13 Answers
13
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C# SQL Server - Passing a list to a stored procedure
...you're using SQL Server 2008, there's a new featured called a User Defined Table Type. Here is an example of how to use it:
Create your User Defined Table Type:
CREATE TYPE [dbo].[StringList] AS TABLE(
[Item] [NVARCHAR](MAX) NULL
);
Next you need to use it properly in your stored procedure:...
How can I export tables to Excel from a webpage [closed]
How can I export tables to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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TSQL Pivot without aggregate function
I have a table like this...
9 Answers
9
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Get the last inserted row ID (with SQL statement) [duplicate]
I want to get the new created ID when you insert a new record in table.
3 Answers
3
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What is the reason not to use select *?
...nt, the SQL execution engine will error if that column is removed from the table and the query is executed.
You can more easily scan code where that column is being used.
You should always write queries to bring back the least amount of information.
As others mention if you use ordinal column access...