嵌入式动态SQL

1.表管理

表创建，表删除，表修改，无动态输入条件即无宿主变量参与。

例如创建表ln001

EXEC SQL EXECUTE IMMEDIATE "CREATE TABLE ln001 (name VARCHAR(20), sex char(2),certinum varchar(18))" ;

2.表查询

2.1 有固定有效查询条件，无取值操作。

PREPARE,EXECUTE 用法：

EXEC SQL BEGIN DECLARE SECTION;

char sql[256+1];

EXEC SQL END DECLARE SECTION;

memset(sql,0x00,sizeof(sql));

sprintf(sql," delete *from ln001 where certinum='%s' ",certinum);

EXEC SQL PREPARE sql_pre FROM :sql;

EXEC SQL EXECUTE sql_pre;

if(SQLCODE && SQLCODE!=100)

{

PRINTF(__FILE__,__LINE__,"执行sql出错SQLCODE[%d]",SQLCODE);

return -1;

}

2.2 有不定项可选查询条件取多条数据，取值到宿主变量校验。

EXEC SQL BEGIN DECLARE SECTION;

char sql[256+1];

char name[40+1];

short id=0;

EXEC SQL END DECLARE SECTION;

memset(sql,0x00,sizeof(sql));

memset(name,0x00,sizeof(name));

strcpy(sql,"select name from ln001 where 1=1 ");

if(strlen(certinum)>0)

{

sprintf(sql," %s and certinum='%s' ",sql,argv[1]);

}

if(strlen(sex)>0)

{

sprintf(sql," %s and sex='%s' ",sql,argv[2]);

}

EXEC SQL PREPARE sql_pre FROM :sql;

EXEC SQL DECLARE SQL_CUR CURSOR FOR sql_pre;

if(SQLCODE)

{

}

EXEC SQL OPEN SQL_CUR;

if(SQLCODE)

{

}

WHILE(1)

{

EXEC SQL FETCH SQL_CUR INTO:certinum:id;

if(SQLCODE && SQLCODE!=100)

{

PRINTF(__FILE__,__LINE__,"执行sql出错SQLCODE[%d]",SQLCODE);

EXEC SQL CLOSE SQL_CUR;

return -1;

}

if(SQLCODE=100)

{

break;

}

}

EXEC SQL CLOSE SQL_CUR;