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Select last row in MySQL
How can I SELECT the last row in a MySQL table?
10 Answers
10
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sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...
Set selected option of select box
I want to set a option that was selected previously to be displayed on page load. I tried it with the following code:
16 An...
半个汉字的校验与处理(C++) - C/C++ - 清泛网 - 专注C/C++及内核技术
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// strSrc: 原始字符串
// nMaxLen: 截断后的最大长度
char *GetTruncate(char *strSrc, int nMaxLen)
{
if (strSrc == NULL || nMaxLen == 0)
{
return NULL;
}
int len = strlen(strSrc);
if (len == 0)
{
...
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
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You are so close! All you need to do is select BOTH the home and its max date time, then join back to the topten table on BOTH fields:
SELECT tt.*
FROM topten tt
INNER JOIN
(SELECT home, MAX(datetime) AS MaxDateTime
FROM topten
GROUP BY home) groupedtt...
How to convert std::string to NSString?
...even fairly straightforward NSString content --- for instance, punctuation characters with a bidirectional encoding. */
– cyrilchampier
Nov 4 '12 at 15:14
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1052: Column 'id' in field list is ambiguous
...and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
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Should I use static_cast or reinterpret_cast when casting a void* to whatever
...g between pointer types (as is fairly common when indexing in memory via a char*, for example), static_cast will generate a compiler error and you'll be forced to use reinterpret_cast anyway.
In practice I use reinterpret_cast because it's more descriptive of the intent of the cast operation. You c...
(-2147483648> 0) returns true in C++?
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@RichardJ.RossIII - with clang you are probably getting a 64-bit-typed literal, since it was too big to fit in an int. OP's implementation may not have a 64-bit type.
– Carl Norum
Feb 4 '1...
Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...