sql - "Invalid Column Name"即使列已创建？

Question

我创建了一个表:

create table Praktikant(
    Pr_id char not null Primary key,
    Name varchar(100) not null,
    Mbiemri varchar(100) not null,
    Gender char(1) not null,
    Degree varchar(100) not null,
    age int,
    check (age >18),
    foreign key (Pr_id) references Doctor(Dr_id) on update cascade
)

插入:

insert into Praktikant values ('1', 'Kastriot', 'Tusha', 'M', 'Student', 19);
insert into Praktikant values ('2', 'Trim', 'Dalipi', 'M', 'Student', 23);
insert into Praktikant values ('3', 'Elira', 'Rrmoku', 'F', 'Studente', 24);
insert into Praktikant values ('4', 'Qendresa', 'Krasniqi', 'F', 'Studente',20);

查询:

    select age
    from Praktikant
    where age > 23

我不明白为什么会收到此消息:

Msg 207, Level 16, State 1, Line 1
Invalid column name 'age'.

Answer 1

使用此查询获取表信息:

SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = 'Praktikant'

然后找到您的表架构，因为我怀疑您在另一个架构中有两个同名的表。找到架构后，使用此查询来选择信息:

    select age
      from [schema_name].[Praktikant]
     where age > 23

您可以使用此查询来获取要检查的表列列表:

SELECT * FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'Praktikant'