Derby Embedded 数据库异常行为，SQLSyntaxErrorException

Question

我在 Java 项目中有一个嵌入式数据库，其中 table TOOLS_IMAGES 有两列“TOOL_id” (int) 和“TOOL_image”（斑点）。我尝试使用以下代码获取 blob：

rs = stmt.executeQuery("SELECT * FROM 'TOOLS_IMAGES' WHERE 'TOOL_id' = " + id);

该程序尝试通过这种方式一张一张地获取大约 15 张不同的图像。当我运行程序时，它有时设法获得一张图像，有时两张，有时甚至六张，但有时它总是抛出以下异常。在那次失败之后，它会为以下每张图片抛出此异常：

java.sql.SQLSyntaxErrorException: Syntax error: Encountered "\'TOOLS_IMAGES\'" at line 1, column 15.
Caused by: ERROR 42X01: Syntax error: Encountered "\'TOOLS_IMAGES\'" at line 1, column 15.

为什么我在 SQL 查询中使用撇号？我已经在没有它们的情况下尝试过，但是这里 sql 将查询中的所有小写字母转换为大写字母，并在事后抱怨找不到该列 -.- 看起来像这样：

rs = stmt.executeQuery("SELECT * FROM TOOLS_IMAGES WHERE TOOL_id = " + id);

和

java.sql.SQLSyntaxErrorException: Column 'TOOL_ID' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE  statement then 'TOOL_ID' is not a column in the target table.
Caused by: ERROR 42X04: Column 'TOOL_ID' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE  statement then 'TOOL_ID' is not a column in the target table.

编辑：这是我用来创建 table

的脚本

create table TOOLS_IMAGES
(
    "TOOL_id"   INTEGER not null
        constraint TOOLS_IMAGES_PK
            primary key,
    "TOOL_mask" BLOB,
    "TOOL_img"  BLOB
);

Answer 1

尝试使用：

ResultSet rs = stm.executeQuery("SELECT * FROM TOOLS_IMAGES WHERE \"TOOL_id\" = " + 1);

如果你输入：

rs = stmt.executeQuery("SELECT * FROM TOOLS_IMAGES WHERE TOOL_id = " + id);

它将被 Derby 处理为：

rs = stmt.executeQuery("SELECT * FROM TOOLS_IMAGES WHERE TOOL_ID = " + id);

不一样

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Derby Embedded 数据库异常行为，SQLSyntaxErrorException

Derby Embedded database strange behaviour, SQLSyntaxErrorException

java

sql

derby

embedding