Mysql mariaDB语法错误（带有if语句和参数的存储过程）

你好，你好。。 我需要一些关于使用shell或cmd查询存储过程的帮助` 这是我的书桌

如果我使用一个没有If语句的操作，比如下面的查询，它就可以正常工作

但是如果我使用一个if语句并放入一个参数，比如下面的查询

它将返回这样的错误

---

您的代码有很多问题。首先，IF语句需要在条件之后加上一个THEN，并且必须以END IF终止。其次，过程中的所有语句都必须以；结尾；。请尝试以下方法：

create procedure insertUpdateSelectDelete(
    id int(11),
    lname varchar(50),
    fname varchar(50),
    mname varchar(50),
    statementtype varchar(30)
)
begin
    if statementtype = 'Insert' then
        insert into bookAuthor (authorLname,authorFname,authorMname)
        values (lname,fname,mname);
    elseif statementtype = 'Update' then
        update bookAuthor
        set authorLname = lname, authorFname = fname, authorMname = mname
        where authorID = id;
    elseif statementtype = 'Select' then
        select * from bookAuthor;
    elseif statementtype = 'Delete' then
        delete from bookAuthor where authorID = id;
    end if;
end

请注意，如果您像我一样以if/ELSEIF块的形式编写过程，则不需要严格使用BEGIN/END包装器，因为过程中只有一条语句

---

这是一个工作流程图。

@JunCain太好了。很高兴我能帮忙。您缺少分隔符语句。

 MariaDB [library]> create procedure selectAll()
    -> select * from bookAuthor;
Query OK, 0 rows affected (0.60 sec)

 MariaDB [library]> create procedure insertUpdateSelectDelete
    -> (
    -> id int(11),
    -> lname varchar(50),
    -> fname varchar(50),
    -> mname varchar(50),
    -> statementtype varchar(30)
    -> )
    -> if statementtype = 'Insert'
    -> insert into bookAuthor
    -> (
    -> authorLname,
    -> authorFname,
    -> authorMname
    -> )
    -> values
    -> (
    -> lname,
    -> fname,
    -> mname
    -> )
    -> if statementtype = 'Update'
    -> update bookAuthor set
    -> authorLname = lname,
    -> authorFname = fname,
    -> authorMname = mname
    -> where authorID = id
    -> if statementtype = 'Select'
    -> select * from bookAuthor
    -> if statementtype = 'Delete'
    -> delete from bookAuthor where authorID = id;

 ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'insert into bookAuthor
(
authorLname,
authorFname,
authorMname
)
values
(
lname,' at line 10

create procedure insertUpdateSelectDelete(
    id int(11),
    lname varchar(50),
    fname varchar(50),
    mname varchar(50),
    statementtype varchar(30)
)
begin
    if statementtype = 'Insert' then
        insert into bookAuthor (authorLname,authorFname,authorMname)
        values (lname,fname,mname);
    elseif statementtype = 'Update' then
        update bookAuthor
        set authorLname = lname, authorFname = fname, authorMname = mname
        where authorID = id;
    elseif statementtype = 'Select' then
        select * from bookAuthor;
    elseif statementtype = 'Delete' then
        delete from bookAuthor where authorID = id;
    end if;
end