knex.js 介绍
knex.js 是一个查询构建器，用于 Postgresql, MysqL 和 sqlite3。它设计灵活，轻便和有趣。
特性：
-
the ability to run in the Browser
例子：
var knex = require('knex')({
dialect: 'sqlite3',
connection: {
filename: './data.db'
}
});
// Create a table
knex.schema.createTable('users', function(table) {
table.increments('id');
table.string('user_name');
})
// ...and another
.createTable('accounts', function(table) {
table.increments('id');
table.string('account_name');
table.integer('user_id').unsigned().references('users.id');
})
// Then query the table...
.then(function() {
return knex.insert({user_name: 'Tim'}).into('users');
})
// ...and using the insert id, insert into the other table.
.then(function(rows) {
return knex.table('accounts').insert({account_name: 'knex', user_id: rows[0]});
})
// Query both of the rows.
.then(function() {
return knex('users')
.join('accounts', 'users.id', 'accounts.user_id')
.select('users.user_name as user', 'accounts.account_name as account');
})
// .map over the results
.map(function(row) {
console.log(row);
})
// Finally, add a .catch handler for the promise chain
.catch(function(e) {
console.error(e);
});