我正在尝试基于JSON文件创建数据库，但是我弄乱了键和引用。你们可以看看一下，并告诉我create语句有什么问题吗？ json文件基本上是人们的评论或评论，并且此json文件中有7个响应对象和一个光标对象。 JSON文件：
{
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"hasPrev": false,
"total": null,
"id": "1542275432008325:1:0",
"more": false
},
"code": 0,
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"message": "<p>A sinking pound, resignations by the bucketful railroading through a so-called agreement nobody wants. For the good of the country Mrs. May 'go and go now'.</p>",
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"createdAt": "2018-11-15T11:20:37",
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"raw_message": "A sinking pound, resignations by the bucketful railroading through a so-called agreement nobody wants. For the good of the country Mrs. May 'go and go now'.",
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"message": "<p>This could be heaven, or this could be hell.</p>",
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"message": "<p>The crappest of crap deals.<br>Will never get through Parliament.</p><p>You are the weakest link May, goodbye.</p>",
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"raw_message": "The crappest of crap deals.\nWill never get through Parliament.\n\nYou are the weakest link May, goodbye.",
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"message": "<p>We are all just prisoners here of our own device. </p>",
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"raw_message": "We are all just prisoners here of our own device. ",
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"editableUntil": "2018-11-22T10:27:03",
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"message": "<p>Should be no deal end off.<br>Nobody could possibly be the winner so it's simple leave and that's it .<br>Their will always be wannabes who think they can do better in it for only their own powers not for the general country or the people of it .,</p>",
"id": "4196012501",
"createdAt": "2018-11-15T10:27:03",
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"raw_message": "Should be no deal end off.\nNobody could possibly be the winner so it's simple leave and that's it .\nTheir will always be wannabes who think they can do better in it for only their own powers not for the general country or the people of it .,",
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"message": "<p>Damned if she does, damned if she doesn't. All for a cause she does not believe in.<br>She will go down in history whatever happens. <br>The question is: who better to lead the country at such an important juncture??<br>Answers on a postcard!</p>",
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"createdAt": "2018-11-15T10:26:42",
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"raw_message": "Damned if she does, damned if she doesn't. All for a cause she does not believe in.\nShe will go down in history whatever happens. \nThe question is: who better to lead the country at such an important juncture??\nAnswers on a postcard!",
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"message": "<p>Theresa May is using The Eagles Hotel California lyrics as the inspiration for her Brexit plan.</p><p>You can check out any time you like, but you can never leave.</p>",
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SQL语句：
CREATE TABLE cursor(
code DOUBLE NOT NULL,
hasNext VARCHAR(50) NOT NULL,
next VARCHAR(50) NOT NULL,
hasPrev VARCHAR(50) NOT NULL,
id VARCHAR(50) NOT NULL,
more VARCHAR(50) NOT NULL,
PRIMARY KEY (hasNext),
FOREIGN KEY (code) REFERENCES dbjson(code)
)
CREATE TABLE small(
isCustom VARCHAR(50) NOT NULL,
permalink VARCHAR(100) NOT NULL,
cache VARCHAR(100) NOT NULL,
PRIMARY KEY (permalink),
FOREIGN KEY (username) REFERENCES avatar(isCustom)
)
CREATE TABLE moderationLabels(
editableUntil VARCHAR(50) NOT NULL,
FOREIGN KEY (code) REFERENCES response(editableUntil)
)
CREATE TABLE large(
isCustom VARCHAR(50) NOT NULL,
permalink VARCHAR(100) NOT NULL,
cache VARCHAR(100) NOT NULL,
PRIMARY KEY (permalink),
FOREIGN KEY (username) REFERENCES avatar(isCustom)
)
CREATE TABLE response(
code DOUBLE NOT NULL,
editableUntil VARCHAR(50) NOT NULL,
dislikes DOUBLE NOT NULL,
numReports DOUBLE NOT NULL,
likes DOUBLE NOT NULL,
message VARCHAR(200) NOT NULL,
id VARCHAR(50) NOT NULL,
createdAt VARCHAR(50) NOT NULL,
isSpam VARCHAR(50) NOT NULL,
isDeletedByAuthor VARCHAR(50) NOT NULL,
isDeleted VARCHAR(50) NOT NULL,
isApproved VARCHAR(50) NOT NULL,
isFlagged VARCHAR(50) NOT NULL,
raw_message VARCHAR(200) NOT NULL,
isHighlighted VARCHAR(50) NOT NULL,
canVote VARCHAR(50) NOT NULL,
thread VARCHAR(50) NOT NULL,
forum VARCHAR(50) NOT NULL,
points DOUBLE NOT NULL,
isEdited VARCHAR(50) NOT NULL,
sb VARCHAR(50) NOT NULL,
PRIMARY KEY (editableUntil),
FOREIGN KEY (code) REFERENCES dbjson(code)
)
CREATE TABLE author(
editableUntil VARCHAR(50) NOT NULL,
username VARCHAR(50) NOT NULL,
about VARCHAR(50) NOT NULL,
name VARCHAR(50) NOT NULL,
disable3rdPartyTrackers VARCHAR(50) NOT NULL,
isPowerContributor VARCHAR(50) NOT NULL,
joinedAt VARCHAR(50) NOT NULL,
profileUrl VARCHAR(100) NOT NULL,
url VARCHAR(50) NOT NULL,
location VARCHAR(50) NOT NULL,
isPrivate VARCHAR(50) NOT NULL,
signedUrl VARCHAR(50) NOT NULL,
isPrimary VARCHAR(50) NOT NULL,
isAnonymous VARCHAR(50) NOT NULL,
id DOUBLE NOT NULL,
PRIMARY KEY (username),
FOREIGN KEY (code) REFERENCES response(editableUntil)
)
CREATE TABLE avatar(
username VARCHAR(50) NOT NULL,
isCustom VARCHAR(50) NOT NULL,
permalink VARCHAR(100) NOT NULL,
cache VARCHAR(100) NOT NULL,
PRIMARY KEY (isCustom),
FOREIGN KEY (editableUntil) REFERENCES author(username)
)
CREATE TABLE media(
editableUntil VARCHAR(50) NOT NULL,
FOREIGN KEY (code) REFERENCES response(editableUntil)
)
CREATE TABLE dbjson(
code DOUBLE NOT NULL,
PRIMARY KEY (code))
答案 0 :(得分：1)
定义外键时，必须先定义父表，然后才能定义引用它的子表。表的定义顺序是这样的：在创建父表之前，有几个表引用了它们的父表。
下一个问题：cursor是MySQL中的reserved keyword。您必须使用这样的反引号将其定界：
CREATE TABLE `cursor`(
...
下一个问题：几个表在表中不存在的列上声明了外键。例如，author具有：
FOREIGN KEY (code) REFERENCES response(editableUntil)
但是author表没有名为code的列。在表上声明外键之前，该列必须存在于表中。表avatar，small，moderationLabels，large和media中发生相同的问题。