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Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
...
What is the correct way to restore a deleted file from SVN?
...go to TortoiseSVN -> Merge...
Make sure "Merge a range of revisions" is selected, click Next
In the "Revision range to merge" textbox, specify the revision that removed the file
Check the "Reverse merge" checkbox, click Next
Click Merge
That is completely untested, however.
Edited by OP: Thi...
How to Delete using INNER JOIN with SQL Server?
...helpful for you -
DELETE FROM dbo.WorkRecord2
WHERE EmployeeRun IN (
SELECT e.EmployeeNo
FROM dbo.Employee e
WHERE ...
)
Or try this -
DELETE FROM dbo.WorkRecord2
WHERE EXISTS(
SELECT 1
FROM dbo.Employee e
WHERE EmployeeRun = e.EmployeeNo
AND ....
)
...
How to force LINQ Sum() to return 0 while source collection is empty
...word
&& l.Property.PropertyId == PropertyId)
.Select(l => l.Amount)
.DefaultIfEmpty(0)
.Sum();
This way, your query will only select the Amount field. If the collection is empty, it will return one element with the value of 0 and then the sum will ...
CSS selector - element with a given child [duplicate]
I'm looking to make a selector which will select all elements if they have a specific child element. For example, select all <div> with a child <span> .
...
MySQL Select Query - Get only first 10 characters of a value
...
Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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How to find largest objects in a SQL Server database?
...quite a bit understanding and determining the size of indices and tables:
SELECT
t.name AS TableName,
i.name as indexName,
sum(p.rows) as RowCounts,
sum(a.total_pages) as TotalPages,
sum(a.used_pages) as UsedPages,
sum(a.data_pages) as DataPages,
(sum(a.total_pages) *...
How to truncate string using SQL server
...ou only want to return a few characters of your long string, you can use:
select
left(col, 15) + '...' col
from yourtable
See SQL Fiddle with Demo.
This will return the first 15 characters of the string and then concatenates the ... to the end of it.
If you want to to make sure than strings ...
IntelliJ: Viewing diff of all changed files between local and a git commit/branch
... new UI, click on Show Diff with Working Tree
Next a window will pop up. Select Files and press cmd + d
Another window which shows diff. You can perform many different types of diff. Use cmd + shift + ] and cmd + shift + [ to shift between files.
Diff Tip: IntelliJ provides advanced diff feat...
How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...