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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...
SQLite table constraint - unique on multiple columns
... the SQLite website, but no examples and my code is crashing. I have other tables with unique constraints on a single column, but I want to add a constraint to the table on two columns. This is what I have that is causing an SQLiteException with the message "syntax error".
...
Populate data table from data reader
...
You can load a DataTable directly from a data reader using the Load() method that accepts an IDataReader.
var dataReader = cmd.ExecuteReader();
var dataTable = new DataTable();
dataTable.Load(dataReader);
...
Is there an equivalent of CSS max-width that works in HTML emails?
...perly in all widely used email clients. I'm wrapping the whole email in a table, and I'd like it to have a width that is up to 98% of the available width, but no greater than 800 pixels. Like this:
<table style="width:98%; max-width:800px;">
...
How to move a model between two Django apps (Django 1.7)
...on(migrations.Migration):
database_operations = [migrations.AlterModelTable('TheModel', 'newapp_themodel')]
state_operations = [migrations.DeleteModel('TheModel')]
operations = [
migrations.SeparateDatabaseAndState(
database_operations=database_operations,
state_...
SQL exclude a column using SELECT * [except columnA] FROM tableA?
We all know that to select all columns from a table, we can use
41 Answers
41
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Generating an Excel file in ASP.NET [closed]
... Excel features
Do not require an install copy of Excel
Can generate Pivot tables
Can be generated using open source project EPPlus
Cons:
Limited compatibility outside Excel 2007 (shouldn't be a problem nowadays)
Complicated unless you're using a third party component
SpreadSheetML (open form...
How do I rename a column in a database table using SQL?
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On PostgreSQL (and many other RDBMS), you can do it with regular ALTER TABLE statement:
=> SELECT * FROM Test1;
id | foo | bar
----+-----+-----
2 | 1 | 2
=> ALTER TABLE Test1 RENAME COLUMN foo TO baz;
ALTER TABLE
=> SELECT * FROM Test1;
id | baz | bar
----+-----+-----
2 |...
Distinct in Linq based on only one field of the table
...am trying to use .distinct in Linq to get result based on one field of the table (so do not require a whole duplicated records from table).
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Deleting all records in a database table
How do I delete all records in one of my database tables in a Ruby on Rails app?
7 Answers
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