SQLITE源码剖析(14)

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　　声明：本SQLite源码剖析系列为刘兴(http://deepfuture.iyunv.com/)原创，未经笔者授权，任何人和机构不能转载

**sqlite3_exec()回调函数的第2个参数是结果的列数，第3个参数

**是从sqlite3_column_text()获取的每列字符串指针的数组，为相关结果列

** ^The 2nd argument to the sqlite3_exec() callback function is the

** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()

** callback is an array of pointers to strings obtained as if from

** [sqlite3_column_text()], one for each column.  ^If an element of a

** result row is NULL then the corresponding string pointer for the

** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the

** sqlite3_exec() callback is an array of pointers to strings where each

** entry represents the name of corresponding result column as obtained

** from [sqlite3_column_name()].

**如果结果行的一个元素是NULL，则sqlite3_exec()回调的相应字符串指针

**是NULL。sqlite3_exec() 回调的第4个参数是字符串指针的数组，为相关结果列的名称，从sqlite3_column_name()获得

** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer

** to an empty string, or a pointer that contains only whitespace and/or

** SQL comments, then no SQL statements are evaluated and the database

** is not changed.

**如果sqlite3_exec()的第2个参数(SQL语句)为空指针、空字符串或仅包含空格的SQL，则没有SQL语句被 执行，数据库不会改变。