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Resolve build errors due to circular dependency amongst classes
...o handle the forward declarations. The only "disadvantage" would be in the extra files. I assume you always include a.fwd.h in a.h, to assure they stay in sync. The example code is missing where these classes are used. a.h and b.h will both need to be included since they won't function in isolatio...
How to change the CHARACTER SET (and COLLATION) throughout a database?
...DEFAULT is not null, CONCAT(' DEFAULT \'', COLUMN_DEFAULT, '\''), ''), if (EXTRA != '', CONCAT(' ', EXTRA), '')))), ';') as alter_statement
FROM information_schema.columns a
INNER JOIN INFORMATION_SCHEMA.TABLES b ON a.TABLE_CATALOG = b.TABLE_CATALOG
AND a.TABLE_SCHEMA = b.TABLE_SCHEM...
How do I escape a single quote in SQL Server?
...ative is using double quote characters, instead of single ones, around the string. I.e.,
insert into my_table values("hi, my name's tim.");
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lua和c/c++互相调用实例分析 - C/C++ - 清泛网 - 专注C/C++及内核技术
...;
void (lua_pushinteger) (lua_State *L, lua_Integer n);
void (lua_pushlstring) (lua_State *L, const char *s, size_t l);
void (lua_pushstring) (lua_State *L, const char *s);
void (lua_pushboolean) (lua_State *L, int b);
void (lua_pushcclosure) (lua_State *L, lua_CFunction fn, int n);
数...
Why can Java Collections not directly store Primitives types?
...tion of primitives. Even in the few cases where I might have wanted to the extra time and space costs of using the reference objects has been negligible. In particular I find that many people think they want Map<int,T>, forgetting that an array will do that trick very nicely.
...
How to remove first 10 characters from a string?
How to ignore the first 10 characters of a string?
12 Answers
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Are there disadvantages to using a generic varchar(255) for all text-based fields?
... (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
...
Equals(=) vs. LIKE
... these operators!
= is a comparison operator that operates on numbers and strings. When comparing strings, the comparison operator compares whole strings.
LIKE is a string operator that compares character by character.
To complicate matters, both operators use a collation which can have important...
Group query results by month and year in postgresql
...ht make sense to use date_trunc, but in some cases having a formatted date string is preferable, and if you're using a performant data warehouse the additional computation might not be a deal breaker. For example, if you are running a quick analytics report using redshift, and it usually takes 3 sec...
Please explain the exec() function and its family
... family have different behaviours:
l : arguments are passed as a list of strings to the main()
v : arguments are passed as an array of strings to the main()
p : path/s to search for the new running program
e : the environment can be specified by the caller
You can mix them, therefore you have:
...