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Change Schema Name Of Table In SQL
I want to change schema name of table Employees in Database. In the current table Employees database schema name is dbo I want to change it to exe . How can I do it ?
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Is SQL syntax case sensitive?
...OM, WHERE, etc), but are often written in all caps. However in some setups table and column names are case-sensitive. MySQL has a configuration option to enable/disable it. Usually case-sensitive table and column names are the default on Linux MySQL and case-insensitive used to be the default on Win...
Rails auto-assigning id that already exists
...to set the sequence for your company.id column to the highest value in the table with a query like this:
SELECT setval('company_id_seq', (SELECT max(id) FROM company));
I am guessing at your sequence name "company_id_seq", table name "company", and column name "id" ... please replace them with th...
What are the differences between virtual memory and physical memory?
...perating system creates and deals with these mappings - utilizing the page table, among other data structures to maintain the mappings. Virtual memory mappings are always found in the page table or some similar data structure (in case of other implementations of virtual memory, we maybe shouldn't ca...
Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
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In JavaScript, why is “0” equal to false, but when tested by 'if' it is not false by itself?
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Tables displaying the issue:
and ==
Moral of the story use ===
table generation credit: https://github.com/dorey/JavaScript-Equality-Table
sha...
Why would someone use WHERE 1=1 AND in a SQL clause?
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Indirectly Relevant: when 1=2 is used:
CREATE TABLE New_table_name
as
select *
FROM Old_table_name
WHERE 1 = 2;
this will create a new table with same schema as old table. (Very handy if you want to load some data for compares)
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Remove Trailing Spaces and Update in Columns in SQL Server
I have trailing spaces in a column in a SQL Server table called Company Name .
13 Answers
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How to Delete using INNER JOIN with SQL Server?
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You need to specify what table you are deleting from, here is a version with an alias:
DELETE w
FROM WorkRecord2 w
INNER JOIN Employee e
ON EmployeeRun=EmployeeNo
WHERE Company = '1' AND Date = '2013-05-06'
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How is set() implemented?
...zation(s) that exploit this lack of values
So basically a set uses a hashtable as its underlying data structure. This explains the O(1) membership checking, since looking up an item in a hashtable is an O(1) operation, on average.
If you are so inclined you can even browse the CPython source code...