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SQL Server Insert if not exists
..., Assunto, Data)
VALUES (@_DE, @_ASSUNTO, @_DATA)
WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos
WHERE De = @_DE
AND Assunto = @_ASSUNTO
AND Data = @_DATA);
END
replace with
BEGIN
IF NOT EXISTS (SELECT * FROM EmailsRecebidos
...
MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
What is the bit size of long on 64-bit Windows?
...bit' and 'long, pointers are 64-bit'.
Type ILP64 LP64 LLP64
char 8 8 8
short 16 16 16
int 64 32 32
long 64 64 32
long long 64 64 64
pointer 64 64 64
The ILP64 sys...
How to create a MySQL hierarchical recursive query
... or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inner join cte
...
How to convert a column number (e.g. 127) into an Excel column (e.g. AA)
... {
modulo = (dividend - 1) % 26;
columnName = Convert.ToChar(65 + modulo).ToString() + columnName;
dividend = (int)((dividend - modulo) / 26);
}
return columnName;
}
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What is the difference between CHARACTER VARYING and VARCHAR in PostgreSQL?
John uses CHARACTER VARYING in the places where I use VARCHAR .
I am a beginner, while he is an expert.
This suggests me that there is something which I do not know.
...
Why is the use of alloca() not considered good practice?
...of the program's execution.
In the header file:
void DoSomething() {
wchar_t* pStr = alloca(100);
//......
}
In the implementation file:
void Process() {
for (i = 0; i < 1000000; i++) {
DoSomething();
}
}
So what happened was the compiler inlined DoSomething function and a...
What does “%.*s” mean in printf?
...f(), rather than hard coding it into the format string, i.e.
void f(const char *str, int str_len)
{
printf("%.*s\n", str_len, str);
}
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follow...
MySQL select one column DISTINCT, with corresponding other columns
I want to select DISTINCT results from the FirstName column, but I need the corresponding ID and LastName .
12 Answe...
Extracting an attribute value with beautifulsoup
...have a question about parsing the output which i a long bunch of non-ASCII chars but I will ask this in a separate question.
– Barnabe
Apr 10 '10 at 7:33
3
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