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In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
7 3 2
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How to get the insert ID in JDBC?
...or Oracle, you can invoke a CallableStatement with a RETURNING clause or a SELECT CURRVAL(sequencename) (or whatever DB-specific syntax to do so) directly after the INSERT in the same transaction to obtain the last generated key. See also this answer.
...
How to export DataTable to Excel
...tring[] columnNames = dataTable.Columns
.Cast<DataColumn>()
.Select(column => column.ColumnName)
.ToArray();
var header = string.Join(",", columnNames.Select(name => $"\"{name}\""));
lines.Add(header);
var valueLines = dataTable.AsEnumerable()
.Select(row => string.J...
Removing “NUL” characters
...id work was closely related:
Open your file in Notepad++
Type Control-A (select all)
Type Control-H (replace)
In 'Find What' type \x00
In 'Replace With' leave BLANK
In 'Search Mode' Selected 'Extended'
Then Click on 'Replace All'
...
Identity increment is jumping in SQL Server database
... the SQL Server.
The solution is:
Run SQL Server Configuration Manager.
Select SQL Server Services.
Right-click SQL Server and select Properties.
In the opening window under Startup Parameters, type -T272 and click Add, then press Apply button and restart.
...
MySql export schema without data
...e the view definition. So if yo had a view like following
create view v1
select `a`.`id` AS `id`,
`a`.`created_date` AS `created_date`
from t1;
with --no-data option, view definition will get changed to following
create view v1
select 1 AS `id`, 1 AS `created_date`
...
How do I break a string across more than one line of code in JavaScript?
...n your example, you can break the string into two pieces:
alert ( "Please Select file"
+ " to delete");
Or, when it's a string, as in your case, you can use a backslash as @Gumbo suggested:
alert ( "Please Select file\
to delete");
Note that this backslash approach is not necessarily preferr...
Types in MySQL: BigInt(20) vs Int(20)
...E TABLE foo ( bar INT(20) ZEROFILL );
INSERT INTO foo (bar) VALUES (1234);
SELECT bar from foo;
+----------------------+
| bar |
+----------------------+
| 00000000000000001234 |
+----------------------+
It's a common source of confusion for MySQL users to see INT(20) and assume ...
Beautiful Soup and extracting a div and its contents by ID
...
Beautiful Soup 4 supports most CSS selectors with the .select() method, therefore you can use an id selector such as:
soup.select('#articlebody')
If you need to specify the element's type, you can add a type selector before the id selector:
soup.select('di...
MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
...statement insert rows based on explicitly specified values. The INSERT ... SELECT form inserts rows selected from another table or tables.
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