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Change One Cell's Data in mysql
How can I change the data in only one cell of a mysql table.
I have problem with UPDATE because it makes all the parameters in a column change but I want only one changed. How?
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Selecting data from two different servers in SQL Server
...edserver.
You only have to set up one. Once you have that, you can call a table on the other server like so:
select
*
from
LocalTable,
[OtherServerName].[OtherDB].[dbo].[OtherTable]
Note that the owner isn't always dbo, so make sure to replace it with whatever schema you use.
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SQL Query to concatenate column values from multiple rows in Oracle
...es of the ename column (concatenated with a comma) from the employee_names table in an xml element (with tag E)
extract the text of this
aggregate the xml (concatenate it)
call the resulting column "Result"
share
|...
What is the easiest way to ignore a JPA field during persistence?
... For Collection type fields, hibernate actually creates a new intermediate table. Any workaround for that ?
– zulkarnain shah
Aug 29 '17 at 9:12
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How do I escape reserved words used as column names? MySQL/Create Table
I am generating tables from classes in .NET and one problem is a class may have a field name key which is a reserved MySQL keyword. How do I escape it in a create table statement? (Note: The other problem below is text must be a fixed size to be indexed/unique)
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Is there a typical state machine implementation pattern?
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I prefer to use a table driven approach for most state machines:
typedef enum { STATE_INITIAL, STATE_FOO, STATE_BAR, NUM_STATES } state_t;
typedef struct instance_data instance_data_t;
typedef state_t state_func_t( instance_data_t *data );
s...
SQL Server: SELECT only the rows with MAX(DATE)
I have a table of data (the db is MSSQL):
11 Answers
11
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Does MySQL ignore null values on unique constraints?
... MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL...
SQL Server query - Selecting COUNT(*) with DISTINCT
In SQL Server 2005 I have a table cm_production that lists all the code that's been put into production. The table has a ticket_number, program_type, and program_name and push_number along with some other columns.
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Simulating group_concat MySQL function in Microsoft SQL Server 2005?
...to do this. Lots of ideas out there, though.
Best one I've found:
SELECT table_name, LEFT(column_names , LEN(column_names )-1) AS column_names
FROM information_schema.columns AS extern
CROSS APPLY
(
SELECT column_name + ','
FROM information_schema.columns AS intern
WHERE extern.table_n...