Postgresql 中文操作指南
Description
TYPE 命令定义一个新的 C 类型。它等同于将 typedef 放入声明部分。
The TYPE command defines a new C type. It is equivalent to putting a typedef into a declare section.
只有 ecpg 在 -c 选项下运行时才会识别此命令。
This command is only recognized when ecpg is run with the -c option.
Examples
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];下面是一个使用 EXEC SQL TYPE 的示例程序：
Here is an example program that uses EXEC SQL TYPE:
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;
}该程序的输出如下所示：
The output from this program looks like this:
t.v = testdb
t.i = 256
t_ind.v_ind = 0
t_ind.i_ind = 0