C中mysql_query(INSERT INTO table() values(ch,……)

[johndiyang]

C语言中mysql_query(INSERT INTO table() values(ch,……)
ch 的定义是char ch=‘a’;
上边的执行为什么会出错？怎么样通过参数变量插入记录？

mysql_query(INSERT INTO table() values('ch',……) 这一句不会出错！

[itblog]

反正是char型的变量都要加上''，这是约定。
mysql_query(INSERT INTO table() values('ch',……)
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你这样写插入的不应该是ch变量的值，应该是ch值吧~

[johndiyang]

mao_kern()
谢谢指点，我看了API，可是还没有看明白。
书上的API例子都是插入值，没有调用变量的！

[johndiyang]

恩，我是用'ch'测试数据库连接是不是正确。
但是怎么通过变量来插入？

[johndiyang]

只要把字符串修改成变量他就会报错。
比如：you have errror in your sql syntax "&ch,now())"
或者 unkonw column 'ch' in(field list)

[mao_kern]

mysql_query(mysql_handler,"insert into table_1(..,..) values('a',..)");
mysql_query第2个参数要求字符串，看看API呀

[mao_kern]

22.2.3.50. mysql_query()
int mysql_query(MYSQL *mysql, const char *query)

Description

Executes the SQL query pointed to by the null-terminated string query. Normally, the string must consist of a single SQL statement and you should not add a terminating semicolon (‘;’) or \g to the statement. If multiple-statement execution has been enabled, the string can contain several statements separated by semicolons. See Section 22.2.9, “C API Handling of Multiple Query Execution”.

mysql_query() cannot be used for queries that contain binary data; you should use mysql_real_query() instead. (Binary data may contain the ‘\0’ character, which mysql_query() interprets as the end of the query string.)

If you want to know whether the query should return a result set, you can use mysql_field_count() to check for this. See Section 22.2.3.22, “mysql_field_count()”.

Return Values

Zero if the query was successful. Non-zero if an error occurred.

[dreamXren]

这样组装一下：
char buffer[256];
memset(buffer, 0, sizeof(buffer));
sprintf(buffer, "INSERT INTO table() values('%c')", ch);
mysql_query(buffer);

[johndiyang]

谢谢各位的指点!