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How can I create a copy of an Oracle table without copying the data?
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Just use a where clause that won't select any rows:
create table xyz_new as select * from xyz where 1=0;
Limitations
The following things will not be copied to the new table:
sequences
triggers
indexes
some constraints may not be copied
materialized view...
SQL Server equivalent to Oracle's CREATE OR REPLACE VIEW
...y create or replace views or stored procedures as follows.
IF NOT EXISTS (SELECT * FROM sys.views WHERE object_id = OBJECT_ID(N'[dbo].[vw_myView]'))
EXEC sp_executesql N'CREATE VIEW [dbo].[vw_myView] AS SELECT ''This is a code stub which will be replaced by an Alter Statement'' as [code_stub]'
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How do I use jQuery's form.serialize but exclude empty fields
... looking over the jQuery docs and I think we can do this in one line using selectors:
$("#myForm :input[value!='']").serialize() // does the job!
Obviously #myForm gets the element with id "myForm" but what was less obvious to me at first was that the space character is needed between #myForm and...
Xcode stops working after set “xcode-select -switch”
...eloper directory, not the Xcode application bundle. Run this:
sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer
With recent versions of Xcode, you can go to Xcode ➙ Preferences… ➙ Locations and pick one of the options for Command Line Tools to set the location.
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What is the best way to add options to a select from a JavaScript object with jQuery?
What is the best method for adding options to a <select> from a JavaScript object using jQuery?
36 Answers
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How to check if a column exists in a SQL Server table?
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SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tabl...
Spring JPA selecting specific columns
...Spring JPA to perform all database operations. However I don't know how to select specific columns from a table in Spring JPA?
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How do I check if a Sql server string is null or empty
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I think this:
SELECT
ISNULL(NULLIF(listing.Offer_Text, ''), company.Offer_Text) AS Offer_Text
FROM ...
is the most elegant solution.
And to break it down a bit in pseudo code:
// a) NULLIF:
if (listing.Offer_Text == '')
temp := nu...
What columns generally make good indexes?
...earching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such columns should be indexed against which yo...
Installing Python 3 on RHEL
... As I said, the link in your answer contains non-printable unicode characters. When I copy/paste your link, here is what I see in VIM: https://dl.iuscommunity.org/pub/ius/stable/CentOS/6/x86_64/iu<200c><200b>s-release-1.0-14.ius.centos6.noarch.rpm Here is the unicode cha...