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How to get the connection String from a database
... Visual Studio go to Tools -> Connect to Database.
2] Under Server Name Select your Database Server Name (Let the list Populate if its taking time).
3] Under Connect to a Database, Select Select or enter a database name.
4] Select your Database from Dropdown.
5] After selecting Database try Test ...
Count(*) vs Count(1) - SQL Server
...
The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
Converting an array of objects to ActiveRecord::Relation
...e clause will generate a SQL statement with IN that looks something like:
SELECT .... WHERE `my_models`.id IN (2, 3, 4, 6, ....
Keep in mind that the ordering of the array will be lost - But since your objective is only to run a class method on the collection of these objects, I assume it won't b...
An explicit value for the identity column in table can only be specified when a column list is used
...tead of
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table
SELECT *
FROM source_table;
SET IDENTITY_INSERT archive_table OFF;
you need to write
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table (field1, field2, ...)
SELECT field1, field2, ...
FROM source_table;...
How do I remove the first characters of a specific column in a table?
...
SELECT RIGHT(MyColumn, LEN(MyColumn) - 4) AS MyTrimmedColumn
Edit:
To explain, RIGHT takes 2 arguments - the string (or column) to operate on, and the number of characters to return (starting at the "right" side of the stri...
Cannot find Dumpbin.exe
... Search for "command prompt" in the start menu, which brings up a selection of command prompts. Look for "Visual C++" or "Developer Studio" command prompts.
– edW
Feb 17 '19 at 23:26
...
Ora-00257 错误处理一列 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
.../oracle/.bash_profile
进入ORLACE
sqlplus /as sysdba
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC
---------- ---------- ---------- ---------- ---------- ---------- ---
STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE#...
Is it possible to apply CSS to half of a character?
.../
overflow: hidden;
pointer-events: none; /* so the base char is selectable by mouse */
color: #f00; /* for demo purposes */
text-shadow: 2px -2px 0px #af0; /* for demo purposes */
}
.halfStyle:after { /* creates the right part */
display: block;
direction: rtl; /* ...
Difference between / and /* in servlet mapping url pattern
...tial difference between /* and / is that a servlet with mapping /* will be selected before any servlet with an extension mapping (like *.html), while a servlet with mapping / will be selected only after extension mappings are considered (and will be used for any request which doesn't match anything ...
In MySQL queries, why use join instead of where?
...FROM clause
Write the association between the tables in the WHERE clause
SELECT *
FROM TABLE_A a,
TABLE_B b
WHERE a.id = b.id
Here's the query re-written using ANSI-92 JOIN syntax:
SELECT *
FROM TABLE_A a
JOIN TABLE_B b ON b.id = a.id
From a Performance Perspective:
Where su...