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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...
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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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...
How to automatically navigate to the current class in Intellij Idea Project Tool Window?
...expands to show the currently open class (or file), and this class becomes selected in the tree.
6 Answers
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Is there a CSS parent selector?
How do I select the <li> element that is a direct parent of the anchor element?
33 Answers
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Getting a map() to return a list in Python 3.x
...You can wrap the above in list if you really need a list of the individual characters, but since str is already an iterable of its own characters, the only reason you'd do so is if you need mutability.
– ShadowRanger
Jul 1 '16 at 1:52
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Which version of PostgreSQL am I running?
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Run this query from PostgreSQL:
SELECT version();
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How to make a select with array contains value clause in psql
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Try
SELECT * FROM table WHERE arr @> ARRAY['s']::varchar[]
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Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
How Do I Choose Between a Hash Table and a Trie (Prefix Tree)?
...(1) (in relation to the upper bound). Maybe the longest english word is 50 characters?
8 Answers
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