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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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Eclipse comment/uncomment shortcut?
... Ctrl + / and for multiple line comment you can use Ctrl + Shift + / after selecting the lines you want to comment in java editor.
On Mac/OS X you can use ⌘ + / to comment out single lines or selected blocks.
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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
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UUID max character length
... primary key for out oracle DB, and trying to determine an appropriate max character length for the VARCHAR. Apparently this is 36 characters but we have noticed UUID'S generated which are longer than this - up to 60 characters in length.
Does anyone know a suitable max char length for UUID??
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const char* concatenation
I need to concatenate two const chars like these:
12 Answers
12
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How to profile a bash shell script slow startup?
...e set -x later and set +x earlier (or bracket several sections of interest selectively).
Although it's not as fine-grained as GNU date's nanoseconds, Bash 5 includes a variable which gives the time in microseconds. Using it saves you from spawning an external executable for every line and works on ...
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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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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Are there disadvantages to using a generic varchar(255) for all text-based fields?
...e , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothe...