bigint

MySQL数据类型选择 一 .选择原则 更小的通常更好 ：一般情况下选择可以正确存储数据的最小数据类型。越小的数据类型通常更快，占用磁盘，内存和CPU缓存更小。 简单就好 ：简单的数据类型的操作通常需要更少的CPU周期。例如：整型比字符操作代价要小得多，因为字符集和校对规则(排序规则)使字符比整型比较更加复杂。 尽量避免NULL :尽量制定列为NOT NULL，除非真的需要NULL类型的值。因为可能为NULL列使得索引，索引统计和值比较都更复杂。可为NULL的列会使用更多的存储空间，在MySQL里也需要特殊处理。 二.选择具体数据类型 在选择列的数据类型时需要先选定合适的大类型,如：数字，字符串，时间等。 整数类型 有两种类型的数字：整数和实数。如果需要存储整数，可以选择一下集中数据类型： 数据类型 长度/字节 范围 说明 TINYINT 1 -2^7—2^7-1 整数类型可选UNSIGND属性 SMALLINT 2 -2^15—2^15-1 表示不允许为负值 MEDIUMINT 3 -2^23—2^23-1 这大致可以使整数上限提高一倍 INT 4 -2^31—2^31-1 例如UNSIGNED可以使TINYINT BIGINT 8 -2^63—2^63-1 存储的范围是0—255 *实数类型 实数是带有小数部分的数字。然而它们不只是存储小数部分

What I am supposed to use when handling a value in C#, which is bigint for an SQL Server database? Patrick Karcher That corresponds to the long (or Int64 ), a 64-bit integer. Although if the number from the database happens to be small enough, and you accidentally use an Int32, etc., you'll be fine. But the Int64 will definitely hold it. And the error you get if you use something smaller and the full size is needed? A stack overflow! Yay! ChaosPandion Int64 maps directly to BigInt . Source Robb Sadler I just had a script that returned the primary key of an insert and used a SELECT @@identity

As noted in the PHP documentation, when json_decode ing a data structure containing long integers, they'll be converted to floats. The workaround is to use JSON_BIGINT_AS_STRING , which preserves them as strings instead. When json_encode ing such values, JSON_NUMERIC_CHECK will encode those numbers back into large integers: $json = '{"foo":283675428357628352}'; $obj = json_decode($json, false, JSON_BIGINT_AS_STRING); $json2 = json_encode($obj, JSON_NUMERIC_CHECK); var_dump($json === $json2); // true Using this method for a correct roundtrip of the data is prone to errors. If a property

When I parse this little piece of JSON { "value" : 9223372036854775807 } that's what I get { hello: 9223372036854776000 } Is there any way to parse it properly? Not with built-in JSON.parse. You'll need to parse it manually and treat values as string (if you want to do arithmetics with them there is bignumber.js ) You can use Douglas Crockford JSON.js library as a base for your parser. EDIT: I created a package for you :) var JSONbig = require('json-bigint'); var json = '{ "value" : 9223372036854775807, "v2": 123 }'; console.log('Input:', json); console.log(''); console.log('node.js bult-in

Game of Connections 这个题也是直接求 卡特兰数 ，不过数据有一点大，不能够直接求，因为杭电不能交 python 不然我就用 python 写了.... 对于这么大的数据，还不能写 python 就只能用 高精度 啦 代码： // Created by CAD on 2019/8/15. #include <bits/stdc++.h> #define mst(name, value) memset(name,value,sizeof(name)) using namespace std; using ll=long long; struct BigInt { const static int mod=1e4; const static int blo=4; int a[600], len; BigInt() { mst(a, 0), len=1; } BigInt(int v) //用int初始化 { mst(a, 0); len=0; do { a[len++]=v%mod; v/=mod; } while (v); } BigInt operator+(const BigInt &b) const //重载加法运算符 { BigInt res; res.len=max(len, b.len); for (int i=0; i<=res.len; ++i)