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How can I change my default database in SQL Server without using MS SQL Server Management Studio?
...nagement Studio by using the 'options' button in the connection dialog and selecting 'master' as the database to connect to. However, whenever I try to do anything in object explorer, it tries to connect using my default database and fails.
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const char* concatenation
I need to concatenate two const chars like these:
12 Answers
12
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What is the meaning of the prefix N in T-SQL statements and when should I use it?
...1. It is an Nvarchar
This query fails to match Exact Value That Exists.
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ'
// 0 result
using prefix N'' fixes it
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ'
// 1 result - found!!!!
Why? Because latin1_general doesn't have big...
Which are more performant, CTE or temporary tables?
...(A INT IDENTITY PRIMARY KEY, B INT , F CHAR(8000) NULL);
INSERT INTO T(B)
SELECT TOP (1000000) 0 + CAST(NEWID() AS BINARY(4))
FROM master..spt_values v1,
master..spt_values v2;
Example 1
WITH CTE1 AS
(
SELECT A,
ABS(B) AS Abs_B,
F
FROM T
)
SELECT *
FROM CTE1
WHERE A = 780
...
PostgreSQL Crosstab Query
... - not fit for missing attributes
crosstab(text) with 1 input parameter:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inacti...
uint8_t vs unsigned char
What is the advantage of using uint8_t over unsigned char in C?
8 Answers
8
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What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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Storing SHA1 hash values in MySQL
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I would use VARCHAR for variable length data, but not with fixed length data. Because a SHA-1 value is always 160 bit long, the VARCHAR would just waste an additional byte for the length of the fixed-length field.
And I also wouldn’t sto...
Creating Unicode character from its number
I want to display a Unicode character in Java. If I do this, it works just fine:
13 Answers
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urlencode vs rawurlencode?
...ction.rawurlencode.php)
Returns a string in which all non-alphanumeric characters except -_.~ have been replaced with a percent (%) sign followed by two hex digits. This is the encoding described in » RFC 3986 for protecting literal characters from being interpreted as special URL delimiters, a...