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What are the main performance differences between varchar and nvarchar SQL Server data types?
... AND ([URLa] IS NULL OR [URLu] IS NULL))
);
In this model you only SELECT from the [URL] computed column. For inserting and updating, you determine which field to use by seeing if converting alters the incoming value, which has to be of NVARCHAR type:
INSERT INTO TableName (..., URLa, URLu)...
Limit number of characters allowed in form input text field
How do I limit or restrict the user to only enter a maximum of five characters in the textbox?
13 Answers
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How do I make a textbox that only accepts numbers?
...his kind of validation by overloading the KeyPress event and just removing characters which didn't fit the specification. I've looked at the MaskedTextBox control but I'd like a more general solution that could work with perhaps a regular expression, or depend on the values of other controls.
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What do single quotes do in C++ when used on multiple characters?
...
It's a multi-character literal. 1952805748 is 0x74657374, which decomposes as
0x74 -> 't'
0x65 -> 'e'
0x73 -> 's'
0x74 -> 't'
Edit:
C++ standard, §2.14.3/1 - Character literals
(...) An ordinary character literal that conta...
Get a substring of a char* [duplicate]
...
char subbuff[5];
memcpy( subbuff, &buff[10], 4 );
subbuff[4] = '\0';
Job done :)
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Is there a way to get rid of accents and convert a whole string to regular letters?
...ble" deconstruction
This will separate all of the accent marks from the characters. Then, you just need to compare each character against being a letter and throw out the ones that aren't.
string = string.replaceAll("[^\\p{ASCII}]", "");
If your text is in unicode, you should use this instead...
Convert seconds to Hour:Minute:Second
...ed to that of the TIME data type, which is from -838:59:59 to 838:59:59 :
SELECT SEC_TO_TIME(8525);
# 02:22:05
See: SEC_TO_TIME
Run the Demo
PostgreSQL example:
SELECT TO_CHAR('8525 second'::interval, 'HH24:MI:SS');
# 02:22:05
Run the Demo
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List columns with indexes in PostgreSQL
...constraint uk_test3ab unique (a, b));
List indexes and columns indexed:
select
t.relname as table_name,
i.relname as index_name,
a.attname as column_name
from
pg_class t,
pg_class i,
pg_index ix,
pg_attribute a
where
t.oid = ix.indrelid
and i.oid = ix.indexreli...
MySQL: Large VARCHAR vs. TEXT?
... @Pacerier another interesting example is mentioned in the comments of the selected answer, basically he had a front-end limit of 2,000 characters but the characters introduced were in a codepage that in reality used more bytes than normal letters, his database ended up needing space for 24k charact...
What is the default value for enum variable?
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Thanks, and what about enums defined with char instead of int. e.g. enum Status { Active = 'A', Inactive='I'}
– Fernando Torres
Apr 24 '15 at 16:17
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