sqlite varchar

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sqlite varchar

This table shows only a small subset of the datatype names that SQLite will accept. Note that numeric arguments in parentheses that following the type name (ex: "VARCHAR(255)") are ignored by SQLite - SQLite does not impose any length restrictio,跳到 What is the maximum size of a VARCHAR in SQLite? - SQLite does not enforce the length of a VARCHAR. You can declare a VARCHAR(10) and SQLite will be happy to store a 500-million character string there. And it will keep all 500-million characters intac, 1、SQLite3支持 NULL、INTEGER、REAL(浮点数字)、TEXT(字符串文本)和BLOB(二进制对象)数据类型,虽然它支持的类型虽然只有五种,但实际上sqlite3也接受varchar(n)、char(n)、decimal(p,s) 等数据类型,只不过在运算或保存时会转成对应的五种数据类型。 2、SQLite最大的特点是你可以保存任何类型的数据到 ...,SQLite 使用一个更普遍的动态类型系统。在SQLite 中,值 ... SQLite 存储类每个存储在SQLite 数据库中的值都具有以下存储类之一: 存储类描述NULL值是一个NULL.. ... VARCHAR(255). VARYING CHARACTER(255). NCHAR(55). NATIVE CHARACTER(70). NVARCHAR(100). TEXT. CLOB. TEXT. BLOB. no datatype specified. , 即使SQLite允许忽略数据类型, 但是仍然建议在你的Create Table语句中指定数据类型. 因为数据类型对于你和其他的程序员交流, 或者你准备换掉你的数据库引擎是非常有用的. SQLite支持常见的数据类型, 如: SQL代码. CREATE TABLE ex2(; a VARCHAR(10),; b NVARCHAR(15),; c TEXT,; d INTEGER,; e FLOAT, ..., It doesn't matter. SQLite does not use sizes when declaring the VARCHAR type. In fact, it almost doesn't use the type either. You can store TEXT in an INT column in SQLite. And SQLite will never truncate a TEXT column., Sqlite doesn't place an explicit limit on the length of the VARCHAR , however the maximum length of any string or blob is limited to the maximum length value, which is 1 billion by default. You can increase or decrease this limit as well, though. So , For your specific problem you will have to convert the varchar yourself and the answer can be found in this stackoverflow post: Sqlite convert string to date. sqlite would allow you to use a regular query for a date saved as a varchar - however, you will,In Microsoft SQL Server, VARCHAR is ASCII and NVARCHAR is Unicode (UTF-16). In SQLite, all text is Unicode, so it's not relevant. In any case, SQLite is loosely typed so it wouldn't make a difference anyways. See http://www.sqlite.org/datatype3.ht, 1、CHAR。CHAR存储定长数据很方便,CHAR字段上的索引效率级高,比如定义char(10),那么不论你存储的数据是否达到了10个字节,都要占去10个字节的空间,不足的自动用空格填充。 2、VARCHAR。存储变长数据,但存储效率没有CHAR高。如果一个字段可能的值是不固定长度的,我们只知道它不可能超过10个 ...

相關軟體 SQLite 資訊

SQLite
SQLite 是一個實現自包含,無服務器,零配置,事務 SQL 數據庫引擎的進程內庫。 SQLite 的代碼是在公共領域,因此可以用於任何目的,商業或私人。 SQLite 是世界上應用最廣泛的數據庫,比我們可以計數的應用程序還要多,其中包括幾個備受矚目的項目。選擇版本:SQLite 3.21.0(32 位)SQLite 3.20.1(64 位) SQLite 軟體介紹

sqlite varchar 相關參考資料
Datatypes In SQLite Version 3

This table shows only a small subset of the datatype names that SQLite will accept. Note that numeric arguments in parentheses that following the type name (ex: "VARCHAR(255)") are ignored b...

https://www.sqlite.org

SQLite Frequently Asked Questions

跳到 What is the maximum size of a VARCHAR in SQLite? - SQLite does not enforce the length of a VARCHAR. You can declare a VARCHAR(10) and SQLite will be happy to store a 500-million character string t...

https://www.sqlite.org

[轉]SQLite 類型數據類型@ pcwiki的部落格:: 痞客邦:: - 痞客邦PIXNET

1、SQLite3支持 NULL、INTEGER、REAL(浮点数字)、TEXT(字符串文本)和BLOB(二进制对象)数据类型,虽然它支持的类型虽然只有五种,但实际上sqlite3也接受varchar(n)、char(n)、decimal(p,s) 等数据类型,只不过在运算或保存时会转成对应的五种数据类型。 2、SQLite最大的特点是你可以保存任何类型的数据到 ...

http://pcwiki.pixnet.net

SQLite 数据类型| 菜鸟教程

SQLite 使用一个更普遍的动态类型系统。在SQLite 中,值 ... SQLite 存储类每个存储在SQLite 数据库中的值都具有以下存储类之一: 存储类描述NULL值是一个NULL.. ... VARCHAR(255). VARYING CHARACTER(255). NCHAR(55). NATIVE CHARACTER(70). NVARCHAR(100). TEXT. CLOB. ...

http://www.runoob.com

sqlite 数据类型全面- CSDN博客

即使SQLite允许忽略数据类型, 但是仍然建议在你的Create Table语句中指定数据类型. 因为数据类型对于你和其他的程序员交流, 或者你准备换掉你的数据库引擎是非常有用的. SQLite支持常见的数据类型, 如: SQL代码. CREATE TABLE ex2(; a VARCHAR(10),; b NVARCHAR(15),; c TEXT,; d INTEGER,; e FLOAT...

https://blog.csdn.net

SQLite VARCHAR default size - Stack Overflow

It doesn't matter. SQLite does not use sizes when declaring the VARCHAR type. In fact, it almost doesn't use the type either. You can store TEXT in an INT column in SQLite. And SQLite will ne...

https://stackoverflow.com

sqlite - VARCHAR LENGTH? - Stack Overflow

Sqlite doesn't place an explicit limit on the length of the VARCHAR , however the maximum length of any string or blob is limited to the maximum length value, which is 1 billion by default. You c...

https://stackoverflow.com

sql - SQLite varchar comparison as date - Stack Overflow

For your specific problem you will have to convert the varchar yourself and the answer can be found in this stackoverflow post: Sqlite convert string to date. sqlite would allow you to use a regular ...

https://stackoverflow.com

difference between VARCHAR NVARCHAR in SQLite - Stack Overflow

In Microsoft SQL Server, VARCHAR is ASCII and NVARCHAR is Unicode (UTF-16). In SQLite, all text is Unicode, so it's not relevant. In any case, SQLite is loosely typed so it wouldn't make a dif...

https://stackoverflow.com

sqlite数据库的char,varchar,text,nchar,nvarchar,ntext的区别_雨点点_ ...

1、CHAR。CHAR存储定长数据很方便,CHAR字段上的索引效率级高,比如定义char(10),那么不论你存储的数据是否达到了10个字节,都要占去10个字节的空间,不足的自动用空格填充。 2、VARCHAR。存储变长数据,但存储效率没有CHAR高。如果一个字段可能的值是不固定长度的,我们只知道它不可能超过10个 ...

http://blog.sina.com.cn