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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.
...
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...
How to append a char to a std::string?
...ing fails with the error prog.cpp:5:13: error: invalid conversion from ‘char’ to ‘const char*’
13 Answers
...
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...
const char* concatenation
I need to concatenate two const chars like these:
12 Answers
12
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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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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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Storing SHA1 hash values in MySQL
...
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...
Fetch the row which has the Max value for a column
... multiple rows for the userid where the maximum date is on multiple rows.
select userid,
my_date,
...
from
(
select userid,
my_date,
...
max(my_date) over (partition by userid) max_my_date
from users
)
where my_date = max_my_date
"Analytic functions rock"
Edi...
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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