JavaScript synchronous RDB (Relational database) without SQL
Available in modern browsers, Node.js and Titanium(NEW!).
This ISN'T ORM, but SQL-less RDB implemented in JavaScript!
$ npm install jsrelor
$ curl https://raw.github.com/shinout/jsrel/master/install-jsrel.sh | shFirst, define the schema
var JSRel = require("jsrel");
var db = JSRel.use("dbname", {schema:
{ user: { name : true, is_activated: "on", $uniques: "name"},
book: { title: true, price: 1, author: "user", $indexes: "title" },
}});Second, insert data
var u1 = db.ins('user', {name: 'shinout'});
var u2 = db.ins('user', {name: 'xxxxx', is_activated: false});
var b1 = db.ins('book', {title: 'how to jsrel', price: 10, author: u1});
var b2 = db.ins('book', {title: 'JSRel API doc', price: 20, author_id: u1.id});Find them!
var users = db.find('user', {is_activated: true});Get one!
var shinout = db.one('user', {name: "shinout"});Greater Than, Less Equal!
var booksGreaterThan5 = db.find('book', { price: {gt: 5} } );
var booksLessEqual15 = db.find('book', { price: {le: 15} } );Like xxx%
var booksLikeJS = db.find('book', { title: {like$: "JS"} } );Join!
var usersJoinBooks = db.find('user', {is_activated: true}, {join: "book"});OrderBy! Offset! Limit!
var users = db.find('user', null, {order: "name", limit : 10, offset : 3} );Perpetuation
db.save();Export / Import
var str = db.$export();
var newDB = JSRel.$import("newID", str);dump as SQL!
var sql = db.toSQL();- rich client applications
- tiny serverside applications
- client caching
- mock DB
NOT suitable for applications which require scalability.
Thinking about the separation of the Model layer.
If we connect to DB asynchronously, we must handle lots of callbacks in a model method.
model.getUserBooks = function(name, callback) {
db.find("user", {name: name}, function(err, users) {
db.find("book", {user_id: users[0].id}, callback);
});
};If we access to DB synchoronously, we can easily write human-readable model APIs.
model.getUserBooks = function(name) {
var user = db.find("user", {name: "xxyy"})[0];
return db.find("book", {user_id: user.id});
};Also, synchoronous codes have an advantage of error handling.
###for those who dislike Blocking APIs###
Why not making it standalone using WebWorker (browsers) or child_process.fork() (Node.js)? Then the whole calculation process doesn't affect the main event loop and we can get the result asynchronously.
I prepared another JavaScript library for this purpose.
Then, we can access model methods like
model.getUserBooks("user01", function(err, result) {
})by defining
model.getUserBooks = function(name) {
var user = db.find("user", {name: "xxyy"})[0];
if (!user) return [];
return db.find("book", {user_id: user.id});
};That is, try/catch and asynchronous APIs are automatically created via standalone.
See make it standalone for detailed usage.
$ npm install jsrelfor development in Titanium or web browsers,
$ curl https://raw.github.com/shinout/jsrel/master/install-jsrel.sh | shin browsers,
<script type="text/javascript" src="/path/to/SortedList.js"></script>
<script type="text/javascript" src="/path/to/jsrel.js"></script>in Node.js or Titanium,
var JSRel = require('jsrel');is the way to load the library.
In browsers, the variable "JSRel" is set to global.
In Web Worker,
importScripts('/pathto/SortedList.js', '/pathto/jsrel.js');See also make it standalone.
JSRel internally uses SortedList When installed with npm, it is automatically packed to node_modules/sortedlist Otherwise, it is recommended to run the following command to prepare jsrel and sortedlist.
$ curl https://raw.github.com/shinout/jsrel/master/install-jsrel.sh | shIn Titanium, you have to set jsrel.js and SortedList.js at the top of Resources directory.
JSRel
- JSRel.use(uniqId, options)
- JSRel.$import(uniqId, data_str, options)
- JSRel.uniqIds
- JSRel.isNode
- JSRel.isBrowser
- JSRel.isTitanium
- JSRel.free
- JSRel.remove
instance of JSRel (jsrel)
- jsrel.table(tableName)
- jsrel.save()
- jsrel.$export()
- jsrel.on(eventName, func, options)
- jsrel.off(eventName, func)
- jsrel.toSQL(options)
- jsrel.origin()
- jsrel.id
- jsrel.name
- jsrel.tables
instance of JSRel Table (table)
- table.columns
- table.ins(obj)
- table.upd(obj, options)
- table.find(query, options)
- table.one(id)
- table.one(query, options)
- table.del(id)
- table.del(query)
shortcut
- jsrel.ins(tableName, ...)
- jsrel.upd(tableName, ...)
- jsrel.find(tableName, ...)
- jsrel.one(tableName, ...)
- jsrel.del(tableName, ...)
Creates instance if not exist. Gets previously created instance if already exists.
uniqId is the identifier of the instance, used for storing the data to external system (file system, localStorage and so on). options is as follows.
| key | type | required? | description | example |
|---|---|---|---|---|
| storage | string | no | type of external storages. oneof "mock", file" "local" "session" When running in Node.js or in Titanium, "file" is set by default. uniqId is the path name to save the data to. When running in browsers, "local" is set by default. local means "localStorage", session means "sessionStorage". When running in Web Worker, "mock" is set and no other options can be selected. "mock" saves nothing. This is limitation of Web Worker which cannot access to Web Storages. In this case, exporting the data to the main thread, we can manually handle and store the data. |
"file" |
| schema | object | required | DB schema | (see SCHEMA JSON) |
| reset | boolean | no (default false) | if true, reset db with the given schema. | true |
| autosave | boolean | no (default false) | whether to auto-saving or not | true |
{
tableName1: tableDescription,
tableName2: {
columnName1 : columnDescription,
columnName2 : columnDescription
}
}table description
| key | type | description | example |
| (columnName) | columnDescription | column to set. name limitation Cannot set [id, ins_at, upd_at] as they are already used by default. Cannot set [$indexes, $uniques, $classes] as they make conflict in schema description. Cannot set [str, num, bool, on, off] as they make conflict in column description. Cannot set [join, order, limit, offset, as, where, select, explain] as they make conflict in search options. Cannot include "," or "." as it is used in indexing or searching. Cannot set (RelatedTableName)_id as it is automatically set. |
age: "num" |
|---|---|---|---|
| $indexes | Array | list of indexes. child arrays are lists of columns to make an index. If string given, converted as array with the value |
[["name"], ["firstName", "lastName"]] |
| $uniques | Array | (the same as $indexes, but this means unique index) | [["name", "pass"]] |
| $classes | Array | (the same as $indexes, but this means classified index) | "type_num" |
column description
| example | description |
| {type: "str"} | type is string. type must be one of ["str", "num", "bool", (columnName)] |
|---|---|
| {type: "str", required: false} | type is string, and if not given, null is set. required option is false by default |
| {type: "bool", _default: true} | type is boolean, and if not given, true is set. |
| {type: "num", required: true} | type is number, and if not given, an exception is thrown. |
| "str" | type is string, and not required. |
| "num" | type is number, and not required. |
| "bool" | type is boolean, and not required. |
| true | type is string, and required. |
| false | type is string, and not required. |
| 1 | type is number, and required. |
| 0 | type is number, and not required. |
| "on" | type is boolean, and default value is true. |
| "off" | type is boolean, and default value is false. |
| {type: tableName} | type is the instance of a record in tableName. the column columnName_id is automatically created. We can set columnName_id instead of columnName in insertion and updating. This column is required unless you set required: false. |
| {type: tableName, required: false} | type is the instance of a record in tableName and not required. |
| tableName | type is the instance of a record in tableName and required. |
Imports data_str and creates a new instance with uniqId. data_str must be a stringified JSON generated by jsrel.$export().
if options.force is true, overrides already-existing database, otherwise throws an exception.
Returns instance of JSRel.
As "import" is a reserved word in JavaScript, used "$import" instead.
(ReadOnly boolean) if Node.js, true.
(ReadOnly boolean) if the executing environment has "localStorage" and "sessionStorage" in global scope, true.
(ReadOnly boolean) if Titanium, true.
Free the region of database uniqId. This does not remove data from the storage.
Remove data from the storage and from memory.
Returns a table object whose name is tableName (registered from the schema). If absent, throws an exception.
Saves current data to the storage. Returns jsrel
Exports current data as the format above. Returns data.
As "export" is a reserved word in JavaScript, used "$export" instead.
Registers hook functions. eventName is the name of the event to bind the function func.
| event name | emitted when | arguments to be passed |
|---|---|---|
| ins | data are inserted |
|
| ins:{tablename} | data are inserted into {tablename} |
|
| upd | data are updated |
|
| upd:{tablename} | data are updated in {tablename} |
|
| del | data are deleted |
|
| del:{tablename} | data are deleted in {tablename} |
|
| save:start | at the start of jsrel.save() |
|
| save:end | at the end of jsrel.save() |
|
| option name | type | description | default |
|---|---|---|---|
| unshift | boolean | registers a function to the top of the list | false |
Unregister hook functions registered in eventName. If a function func is registered in eventName hooks, it is removed. If func is null, all functions registered in eventName is removed.
Gets SQL string from the current schema and data.
options
| option name | type | description | default | example |
|---|---|---|---|---|
| noschema | boolean | if true, schema SQLs (create statements) are not generated. | null | true |
| db | boolean or string | if true, create database whose name is id of the db, if string given, the value is set as database's name. | null | true |
| nodrop | boolean | if true, drop statements are not generated. | null | true |
| nodata | boolean | if true, data SQLs (insert statements) are not generated. | null | true |
| type | string | type of RDBs. Currently, "mysql" is only tested. | "mysql" | "mysql" |
| engine | string | MySQL engine (only enabled when options.type is "mysql") | "InnoDB" | "MyISAM" |
| rails (unstable) | boolean | if true, rails-like date format (created_at, inserted_at) is output. | null | true |
Gets the last savedata.
Unless jsrel.save() has been called at least once, null is returned.
var savedata = jsrel.origin();
var newdb = JSRel.$import("new_db", savedata);(ReadOnly) gets id
(ReadOnly) gets name
(ReadOnly) gets list of registered tables
[table1, table2, ...](ReadOnly) gets registered columns in the table
[column1, column2, ...]
Registers a new record. obj must be compatible with columns of the table. Otherwise it throws an exception. Returns an instance of the record. It is NOT the same as the given argument, as the new object contains "id".
Before insertion, Type checking is performed. JSRel tries to cast the data.
Record objects have all columns registered in the table.
In addition, they have id, ins_at, upd_at in their key. These are all automatically set.
ins_at and upd_at are timestamp values and cannot be inserted.
id is auto-incremented unique integer.
We can specify id in insertion.
table.ins({id: 11, name: "iPhone"});When the table already has the same id, an exception is thrown.
OK, let's think upon the following schema.
var schema = { user: {
nickName : true,
fitstName: false,
lastName : false
},
card: {
title : true,
body : true
},
user_card {
user: "user",
card: "card",
owner: {type : "user", required: false}
$uniques: { user_card: ["user", "card"] }
}
}First, inserts users and cards.
var jsrel = JSRel.use('sample', {schema: schema});
var uTable = jsrel.table('user');
var shinout = uTable.ins({nickName: "shinout"});
var nishiko = uTable.ins({nickName: "nishiko"});
var cTable = jsrel.table('card');
var rabbit = uTable.ins({title: "rabbit", body: "It jumps!"});
var pot = uTable.ins({title: "pot", body: "a tiny yellow magic pot"});Then, inserts these relations.
var ucTable = jsrel.table('user_card');
ucTable.ins({ user: shinout, card: rabbit });We can also insert these relation like
ucTable.ins({ user_id: nishiko.id, card_id: pot.id });
ucTable.ins({ user_id: 1, card_id: 2 }); // 1: shinout, 2: potRemember that user_id and card_id are automatically generated and it represent the id column of each instance. When we pass an invalid id to these columns, an exception is thrown.
ucTable.ins({ user_id: 1, card_id: 5 }); // 1: shinout, 5: undefined!When a relation column is not required, we can pass null.
ucTable.ins({ user: nishiko, card_id: 1, owner_id: null });When duplicated, xxxx_id priors to xxxx (where xxxx is the name of the original column).
ucTable.ins({ user: nishiko, user_id: 1, card_id: 1 }); // user_id => 1obj.rel_table = [relObj1, relObj2, ...];
table.ins(obj);relObj1, relObj2 are also inserted to table "rel_table" containing the new id as the external key.
If the main table is related to the rel_table multiply, you must specify the column like
obj["rel_table.relcolumn"] = [relObj1, relObj2, ...];
table.ins(obj);Updates an existing record. obj must contains id key. Only the valid keys (compatible with columns) in obj is updated. Throws no exceptions when you passes invalid keys. Throws an exception when you an invalid value with a valid key.
Returns an instance of the updated record. It is NOT the same as the given argument.
updating related tables
obj.rel_table = [relObj1, relObj2, ...];
table.upd(obj, {append: append});if relObj contains "id" column, updating the object. Otherwise, inserting the object. If options.append is false or not given, already existing related objects are deleted.
If the main table is related to the rel_table multiply, you must specify the column like
obj["rel_table.relcolumn"] = [relObj1, relObj2, ...];
table.upd(obj, {append: append});Selects records. Returns a list of records. query is an object to describe how to fetch records.
| example | description |
| {name: "shinout"} | name must be equal to "shinout" |
|---|---|
| {name: ["shinout", "nishiko"]} | name must be equal to "shinout" or "nishiko" |
| {name: {like$: "shin"}} | name must be like "shin%" |
| {name: {$like: "inout"}} | name must be like "%inout" |
| {name: [{$like: "inout"}, {equal: "nishiko"}] } | name must be like "%inout" AND equals "nishiko" |
| {name: {$like: "inout", equal: "nishiko"} } | name must be like "%inout" AND equals "nishiko" |
| {age: {gt: 24} } | age must be greater than 24 |
| {age: {gt: 24, le: 40} } | age must be greater than 24 and less equal 40 |
| {age: [{ge: 24}, {lt: 40}] } | age must be greater equal 24 or less than 40 |
| {country: {$in: ["Japan", "Korea"] } | country must be one of "Japan", "Korea" (as "in" is a reserved word in JavaScript, used "$in" instead.) |
| {name: "shinout", age : {ge: 70 } | must returns empty until shinout becomes 70 |
options is as follows.
| key | type | description | example |
|---|---|---|---|
| order | mixed | see order description | { name: "asc" } |
| limit | int | the end position of the data | 20 |
| offset | int | offset of the results | 10 |
| join | mixed | see join description | {records.scene: {title : {like$: "ABC"} } |
| select | string (one of column names) | get list of selected columns instead of objects | "title" |
| select | array (list of column names) | get list of object which contains the given columns instead of all columns | ["name", "age"] |
| explain | object | put searching information to the given object | {} |
| example | description |
| "age" | order by age asc |
|---|---|
| {age: "desc"} | order by age desc |
| {age: "desc", name: "asc"} | order by age desc, name asc |
Returns list of instances
[ {id: 1, name: "shinout"}, {id: 2, name: "nishiko"}, ...]sample data
group
| id | name |
| 1 | mindia |
| 2 | ZZZ |
user
| id | name | age | group |
| 1 | shinout | 25 | 1 |
| 2 | nishiko | 28 | 1 |
| 3 | xxx | 39 | 2 |
card
| id | title | body |
| 1 | rabbit | it jumps! |
| 2 | pot | a tiny yellow magic pot |
| 3 | PC | calculating... |
user_card
| id | user | card |
| 1 | 1 | 1 |
| 2 | 2 | 1 |
| 3 | 1 | 2 |
| 4 | 2 | 3 |
| 5 | 3 | 3 |
Fetching N:1 related objects
var result = db.table('user').find({name: "shinout"}, {join: JOIN_VALUE});| No. | JOIN_VALUE | description | result |
| 1 | "group" | get "group" column as object | [{id: 1, name: "shinout", age: 25, group_id: 1, group: {id: 1, name: "mindia"}}] |
|---|---|---|---|
| 2 | {group : true} | get "group" column as object (the same as sample1) | [{id: 1, name: "shinout", age: 25, group_id: 1, group: {id: 1, name: "mindia"}}] |
| 3 | true | get all the related columns as object | [{id: 1, name: "shinout", age: 25, group_id: 1, group: {id: 1, name: "mindia"}}] |
| 4 | {group : {name: {like$: "mind"}}} | get "group" column as object whose name starts at "mind" | [{id: 1, name: "shinout", age: 25, group_id: 1, group: {id: 1, name: "mindia"}}] |
| 5 | {group : {name: "ZZZ"}} | get "group" column as object whose name is equal to "ZZZ" | [] // empty |
Fetching 1:N related objects
var result = db.table('group').find({name: "mindia"}, {join: JOIN_VALUE});
| No. | JOIN_VALUE | description | result |
| 6 | "user.group" | get "user" table objects (setting the related column in "user" table) | [{id: 1, name: "mindia", "user.group": [{id: 1, name: "shinout", age: 25}, {id: 2, name: "nishiko", age: 28}]}] |
|---|---|---|---|
| 7 | "user" | get "user" table objects (if related column is obvious) | [{id: 1, name: "mindia", "user": [{id: 1, name: "shinout", age: 25}, {id: 2, name: "nishiko", age: 28}]}] |
| 8 | {"user.group" : true } | get "user" table objects (the same as sample6) | [{id: 1, name: "mindia", "user.group": [{id: 1, name: "shinout", age: 25}, {id: 2, name: "nishiko", age: 28}]}] |
| 9 | {"user.group" : {age : {gt: 27}} } | get "user" table objects with age greater than 27 | [{id: 1, name: "mindia", "user.group": [{id: 2, name: "nishiko", age: 28}]}] |
| 10 | {"user.group" : {age : {gt: 27}, as: "users"} } | get "user" table objects with age greater than 27, with alias name "users" | [{id: 1, name: "mindia", "users": [{id: 2, name: "nishiko", age: 28}]}] |
| 11 | {"user.group" : {where : {age : {gt: 27}}, as: "users"} } | get "user" table objects with age greater than 27, with alias name "users" (the canonical expression of sample9) | [{id: 1, name: "mindia", "users": [{id: 2, name: "nishiko", age: 28}]}] |
| 12 | {user : {age : {gt: 27}, as: "users"} } | get "user" table objects with age greater than 27, with alias name "users" | [{id: 1, name: "mindia", "users": [{id: 2, name: "nishiko", age: 28}]}] |
| 13 | {user : {age : {gt: 47}, outer: true} } | outer joining. Records containing Empty 1:N subqueries can be remained with the column filled with null. | [{id: 1, name: "mindia", "users": null}] |
| 13 | {user : {age : {gt: 47}, outer: "array"} } | outer joining. Records containing Empty 1:N subqueries can be remained with the column filled with empty array. | [{id: 1, name: "mindia", "users": [] }] |
Fetching N:M related objects
var result = db.table('user').find({name: "shinout"}, {join: JOIN_VALUE});
| 15 | {"card": {via: "user_card"} } | get "card" related through "user_card" | [{id: 1, name: "shinout", "card": [ {id:1, ...}, {id: 3, ...}] }] |
|---|
Gets one object by id.
Gets one result by table.find().
Deletes a record with a given id .
Deletes records with a given query . query is the same argument as table.find(query).
When a record is deleted, related records are also deleted.
Think upon the schema.
First, inserts users, cards and these relations.
var jsrel = JSRel.use('sample', {schema: schema});
var uTable = jsrel.table('user');
var cTable = jsrel.table('card');
var ucTable = jsrel.table('user_card');
var shinout = uTable.ins({nickName: "shinout"});
var nishiko = uTable.ins({nickName: "nishiko"});
var rabbit = uTable.ins({title: "rabbit", body: "It jumps!"});
var pot = uTable.ins({title: "pot", body: "a tiny yellow magic pot"});
ucTable.ins({ user: shinout, card: rabbit });
ucTable.ins({ user: nishiko, card: rabbit });
ucTable.ins({ user: shinout, card: pot });Next, delete shinout.
uTable.del(shinout);Then, the dependent records ( shinout-rabbit, shinout-pot ) are also removed.
ucTable.find().length; // 1 (nishiko-rabbit)- jsrel.ins(tableName, ...)
- jsrel.upd(tableName, ...)
- jsrel.find(tableName, ...)
- jsrel.one(tableName, ...)
- jsrel.del(tableName, ...)
are, select table via jsrel.table(tableName) in the first place. Then run the operation using the remaining arguments.
for example,
jsre.ins('user', {nickName: "shinout"});is completely equivalent to
jsrel.table('user').ins({nickName: "shinout"});standalone is a library to make a worker process / thread which can communicate with master.
Here are the basic concept.
master.js
standalone("worker.js", function(model) {
model.getSongsByArtist("the Beatles", function(err, songs) {
console.log(songs);
});
});worker.js
var db = JSRel.use("xxx", {schema: {
artist: {name: true},
song : {title: true, artist: "artist"}
}});
var btls = db.ins("artist", {name: "the Beatles"});
db.ins("song", {title: "Help!", artist: btls});
db.ins("song", {title: "In My Life", artist: btls});
var model = {
getSongsByArtist: function(name) {
return db.find("artist", {name : name}, {join: "song", select : "song"});
}
};
standalone(model);In master.js, we can use "getSongsByArtist" asynchronously, catching possible errors in err.
In Node.js, standalone spawns a child process.
In browsers, standalone creates a WebWorker instance.
In Titanium, standalone is not supported.
Because Node.js and WebWorker has a different requiring system, We must be careful of loading scripts.
in Node.js (worker.js)
var JSRel = require('jsrel');
var standalone = require('standalone');This is enough.
in browsers (worker.js)
importScripts('/pathto/SortedList.js', '/pathto/jsrel.js', '/pathto/standalone.js');Don't forget to import SortedList (which JSRel depends on).
(The MIT License)
Copyright (c) 2012 SHIN Suzuki shinout310@gmail.com
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.