GaussDB数据库-嵌入式SQL命令：TYPE

功能描述

定义一个新的数据类型。当运行带有-c选项的ecpg的时候，仅仅标识该命令。

语法格式

TYPE type_name IS ctype

参数说明

type_name

数据类型名称。

ctype

C语言数据类型说明。

示例

EXEC SQL TYPE customer IS
    struct
    {
        varchar name[50];
        int     phone;
    };

EXEC SQL TYPE cust_ind IS
    struct ind
    {
        short   name_ind;
        short   phone_ind;
    };

EXEC SQL TYPE c IS char reference;
EXEC SQL TYPE ind IS union { int integer; short smallint; };
EXEC SQL TYPE intarray IS int[AMOUNT];
EXEC SQL TYPE str IS varchar[BUFFERSIZ];
EXEC SQL TYPE string IS char[11];

使用EXEC SQL TYPE的示例：

EXEC SQL WHENEVER SQLERROR SQLPRINT;  
EXEC SQL TYPE tt IS 
    struct 
    { 
        varchar v[256]; 
        int     i; 
    };  
EXEC SQL TYPE tt_ind IS 
    struct ind { 
        short   v_ind; 
        short   i_ind; 
    };  

int main(void) 
{ 
EXEC SQL BEGIN DECLARE SECTION; 
    tt t; 
    tt_ind t_ind; 
EXEC SQL END DECLARE SECTION; 
     EXEC SQL CONNECT TO testdb AS con1; 
     EXEC SQL SELECT pg_catalog.set_config('search_path', '', false); EXEC SQL COMMIT;
     EXEC SQL SELECT current_database(), 256 INTO :t:t_ind LIMIT 1; 

     printf("t.v = %s\n", t.v.arr); 
     printf("t.i = %d\n", t.i); 

     printf("t_ind.v_ind = %d\n", t_ind.v_ind); 
     printf("t_ind.i_ind = %d\n", t_ind.i_ind); 

     EXEC SQL DISCONNECT con1; 

     return 0; 
}

该示例输出为：

t.v = testdb 
t.i = 256 
t_ind.v_ind = 0 
t_ind.i_ind = 0