数据库笔记14---嵌入式SQL语言(3)（哈工大）

偏执的太偏执、 2022-12-20 15:54 208阅读 0赞

本篇内容包括：

1.  动态SQL的概念和作用
2.  SQL语句的动态构造
3.  动态SQL语句的执行方式
4.  数据字典与SQLCA
5.  ODBC/JDBC简介

# 动态SQL语句的构造 #

依据：QBE语言  
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用户给出查询条件，通过动态的构造SQL查询语句,给出相应查询结果

## 示例一 ##

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### 示例小结 ###

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## 示例二 ##

xxx.checked:保存复选框是否被用户选择(true/false)  
xxx.text:保存用户输入的文本

## 动态SQL语句的两种执行方式 ##

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### P-E-U示例 ###

使用:cust\_id替换:dcid

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比较：  
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# 数据字典与SQLDA(了解就行) #

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SQLDA：存储数据库和表的定义信息，是一个内存数据结构  
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