/*简单约束*/

CREATE TABLE IF NOT EXISTS t_student(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, age INTEGER);

CREATE TABLE IF NOT EXISTS t_student(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL, age INTEGER NOT NULL);

CREATE TABLE IF NOT EXISTS t_student(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT UNIQUE, age INTEGER);

CREATE TABLE IF NOT EXISTS t_student(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, age INTEGER DEFAULT );

/*分页*/

SELECT * FROM t_student ORDER BY id ASC LIMIT , ;

/*排序*/

SELECT * FROM t_student WHERE score >  ORDER BY age DESC;

SELECT * FROM t_student WHERE score <  ORDER BY age ASC , score DESC;

/*计量*/

SELECT COUNT(*) FROM t_student WHERE age > ;

/*别名*/

SELECT name as myName, age as myAge, score as myScore FROM t_student;

SELECT name myName, age myAge, score myScore FROM t_student;

SELECT s.name myName, s.age myAge, s.score myScore FROM t_student s WHERE s.age > ;

/*查询*/

SELECT name, age, score FROM t_student;

SELECT * FROM t_student;

/*修改指定数据*/

UPDATE t_student SET name = 'MM' WHERE age = ;

UPDATE t_student SET name = 'WW' WHERE age is ;

UPDATE t_student SET name = 'XXOO' WHERE age < ;

UPDATE t_student SET name = 'NNMM' WHERE age <  and score > ;

/*删除数据*/

DELETE FROM t_student;

/*更新数据*/

UPDATE t_student SET name = 'LNJ';

/*插入数据*/

 INSERT INTO t_student(age, score, name) VALUES ('', , 'jonathan');

 INSERT INTO t_student(name, age) VALUES ('lee', '');

 INSERT INTO t_student(score) VALUES ();

/*插入数据*/

INSERT INTO t_student(name, age, score) VALUES ('lee', '', );

/*添加主键*/

CREATE TABLE IF NOT EXISTS t_student (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, age INTEGER, score REAL);

/*添加主键*/

CREATE TABLE IF NOT EXISTS t_student (id INTEGER, name TEXT, age INTEGER, score REAL, PRIMARY KEY(id));

/*删除表*/

DROP TABLE IF EXISTS t_student;

/*创建表*/

CREATE TABLE IF NOT EXISTS t_student(id INTEGER , name TEXT, age , score REAL);

.打开数据库

int sqlite3_open(

    const char *filename,   // 数据库的文件路径

    sqlite3 **ppDb          // 数据库实例

);

.执行任何SQL语句

int sqlite3_exec(

    sqlite3*,                                  // 一个打开的数据库实例

    const char *sql,                           // 需要执行的SQL语句

    int (*callback)(void*,int,char**,char**),  // SQL语句执行完毕后的回调

    void *,                                    // 回调函数的第1个参数

    char **errmsg                              // 错误信息

);

.检查SQL语句的合法性（查询前的准备）

int sqlite3_prepare_v2(

    sqlite3 *db,            // 数据库实例

    const char *zSql,       // 需要检查的SQL语句

    int nByte,              // SQL语句的最大字节长度

    sqlite3_stmt **ppStmt,  // sqlite3_stmt实例，用来获得数据库数据

    const char **pzTail

);

.查询一行数据

int sqlite3_step(sqlite3_stmt*); // 如果查询到一行数据，就会返回SQLITE_ROW

.利用stmt获得某一字段的值（字段的下标从0开始）

double sqlite3_column_double(sqlite3_stmt*, int iCol);  // 浮点数据

int sqlite3_column_int(sqlite3_stmt*, int iCol); // 整型数据

sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); // 长整型数据

const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); // 二进制文本数据

const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);  // 字符串数据