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Best way to test if a row exists in a MySQL table
...
You could also try EXISTS:
SELECT EXISTS(SELECT * FROM table1 WHERE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything ...
What does “zend_mm_heap corrupted” mean
...#include <stdlib.h>
int main(void) {
void **mem = malloc(sizeof(char)*3);
void *ptr;
/* read past end */
ptr = (char*) mem[5];
/* write past end */
memcpy(mem[5], "whatever", sizeof("whatever"));
/* free invalid pointer */
free((void*) mem[3]);
retur...
Define: What is a HashSet?
...ontains and Remove.) HashSet also provides standard set operations such as union, intersection, and symmetric difference. Take a look here
There are different implementations of Sets. Some make insertion and lookup operations super fast by hashing elements. However, that means that the order in whi...
How to convert a string to integer in C?
...u have it (but remember it's not portable):
long long
strtonum(const char *nptr, long long minval, long long maxval,
const char **errstr);
EDIT
You might also be interested in strtoumax and strtoimax which are standard functions in C99. For example you could say:
uintmax_t num = strto...
How to drop all tables in a SQL Server database?
...VARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS t...
How can I strip first and last double quotes?
... If string is '"' (just one double quote), this will remove the single character. I think this is probably not what is desired, probably Walapa wanted to only remove the double quote if it was matched.
– dbn
Aug 26 '16 at 0:28
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Case insensitive searching in Oracle
...NLS_COMP and NLS_SORT session parameters:
SQL> SET HEADING OFF
SQL> SELECT *
2 FROM NLS_SESSION_PARAMETERS
3 WHERE PARAMETER IN ('NLS_COMP', 'NLS_SORT');
NLS_SORT
BINARY
NLS_COMP
BINARY
SQL>
SQL> SELECT CASE WHEN 'abc'='ABC' THEN 1 ELSE 0 END AS GOT_MATCH
2 FROM DUAL;
...
How can I view all the git repositories on my machine?
...ameter cannot be found that matches parameter name 'Attributes'. At line:1 char:28
– Dewald Swanepoel
Jan 30 '17 at 9:33
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
As the title says, I am trying to insert into one table selecting values from another table and some default values.
5 Ans...
Splitting String with delimiter
...
Oh, and be careful if you're splitting on certain characters like a pipe |. You will need to escape the char stackoverflow.com/questions/3842537/…
– Snekse
Dec 23 '15 at 17:19
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