CREATE

this article provides how to instructions for creating and organizing documents, linking them to associated files, called attachments , and creating map structures for additional document hierarchies attachments in ditto are represented using the attachment data type, which you can use to store binary data, such as images, alongside queryable descriptive information, such as file name and description database operations syncing data across the mesh is an entirely separate process from crud, involving replicating documents across different databases rather than interacting with a single datastore creating documents to insert a document, call the execute api method against the ditto store object and include an insert into query that specifies the document to be inserted ditto does not support nesting documents within documents instead, opt for a foreign key relationship by referencing the document id for more information, see docid\ gdnqbrhlu5u5jzhdkvhvo for example, the following snippet demonstrates how to insert a new document with a single field "color" set to "blue" await ditto store execute( query "insert into cars documents (\ newcar)", arguments \["newcar" \["color" "blue"]]);ditto store execute( "insert into cars documents (\ newcar)", mapof("newcar" to mapof("color" to "blue")))await ditto store execute( "insert into cars documents (\ newcar)", { newcar { color "blue" } } );dittoqueryresult result = (dittoqueryresult) ditto store execute( "insert into cars documents (\ newcar)", collections singletonmap("newcar", collections singletonmap("color", "blue")), );var args = new dictionary\<string, object>(); args add("newcar", new { color = "blue" }); await ditto store executeasync( "insert into cars documents (\ newcar)", args);std map\<std string, std map\<std string, std string>> args; args\["newcar"] = {{"color", "blue"}}; ditto get store() execute( "insert into cars documents (\ newcar)", args);let query result = ditto store() execute( "insert into cars documents (\ newcar)", some(serde json json!({ "newcar" { "color" "blue" } }) into()), ) await?;await ditto store execute( "insert into cars documents (\ newcar)", arguments {"newcar" {"color" "blue"}}, ); to create multiple documents efficiently, batch your create operations in a single operation if desired, supply a document id in your creation request; otherwise, ditto automatically generates and assigns one inserting multiple documents to create multiple documents in a single operation, use the insert into operation as follows let result = await ditto store execute( query "insert into cars documents (\ newcar)", arguments \[ newcar \["color" "blue"] ]); // "507f191e810c19729de860ea" print(result mutateddocumentids()\[0])var result = ditto store execute( "insert into cars documents (\ newcar)", mapof("newcar" to mapof("color" to "blue"))) // "507f191e810c19729de860ea" println(result mutateddocumentids() first())const result = await ditto store execute( "insert into cars documents (\ newcar)", { newcar { color 'blue' } } ); // "507f191e810c19729de860ea" console log(result mutateddocumentids()\[0] value)dittoqueryresult result = (dittoqueryresult) ditto store execute( "insert into cars documents (\ newcar)", collections singletonmap("newcar", collections singletonmap("color", "blue")), new continuation<>() { @nonnull @override public coroutinecontext getcontext() { return emptycoroutinecontext instance; } @override public void resumewith(@nonnull object o) { if (o instanceof result failure) { // handle failure } } } ); // "507f191e810c19729de860ea" system out println(result mutateddocumentids()\[0]);var insertargs = new dictionary\<string, object>(); insertargs add("newcar", new { color = "blue" }); var result = await ditto store executeasync( "insert into cars documents (\ newcar)", insertargs); // "507f191e810c19729de860ea" result mutateddocumentids foreach(id => console writeline(id));std map\<std string, std map\<std string, std string>> args; args\["newcar"] = {{"color", "blue"}}; auto result = ditto get store() execute( "insert into cars documents (\ newcar)", args); // "507f191e810c19729de860ea" std cout << result mutated document ids()\[0] to string();let query result = ditto store() execute( "insert into cars documents (\ car1), (\ car2)" some(serde json json!({ "car1" { "color" "blue" }, "car2" { "color" "red" } }) into()), ) await?;final result = await ditto store execute( "insert into cars documents (\ doc1),(\ doc2)", arguments { "doc1" {"color" 'blue'}, "doc2" {"color" 'red'}, }, ); identifying documents unless manually supplied, ditto automatically generates and assigns the new document a 128‑bit universally unique identifier (uuid) the document identifier is represented as id and serves as the primary key for the document retrieving document ids t o access the ids of the documents affected by the insertion into operation, call the mutateddocumentids method on the result object after the insertion like this let result = await ditto store execute( query "insert into cars documents (\ newcar)", arguments \[ newcar \["color" "blue"] ]); // "507f191e810c19729de860ea" print(result mutateddocumentids()\[0])var result = ditto store execute( "insert into cars documents (\ newcar)", mapof("newcar" to mapof("color" to "blue"))) // "507f191e810c19729de860ea" println(result mutateddocumentids() first())const result = await ditto store execute( "insert into cars documents (\ newcar)", { newcar { color 'blue' } } ); // "507f191e810c19729de860ea" console log(result mutateddocumentids()\[0] value)dittoqueryresult result = (dittoqueryresult) ditto store execute( "insert into cars documents (\ newcar)", collections singletonmap("newcar", collections singletonmap("color", "blue")), new continuation<>() { @nonnull @override public coroutinecontext getcontext() { return emptycoroutinecontext instance; } @override public void resumewith(@nonnull object o) { if (o instanceof result failure) { // handle failure } } } ); // "507f191e810c19729de860ea" system out println(result mutateddocumentids()\[0]);var insertargs = new dictionary\<string, object>(); insertargs add("newcar", new { color = "blue" }); var result = await ditto store executeasync( "insert into cars documents (\ newcar)", insertargs); // "507f191e810c19729de860ea" result mutateddocumentids foreach(id => console writeline(id));std map\<std string, std map\<std string, std string>> args; args\["newcar"] = {{"color", "blue"}}; auto result = ditto get store() execute( "insert into cars documents (\ newcar)", args); // "507f191e810c19729de860ea" std cout << result mutated document ids()\[0] to string();let query result = ditto store() execute( "insert into cars documents (\ newcar)", some(serde json json!({ "newcar" { "color" "blue" } }) into()), ) await?; // "507f191e810c19729de860ea" println!("{}", query result mutated document ids()\[0] to string())final result = await ditto store execute( "insert into cars documents (\ newcar)", arguments { "newcar" {"color" 'blue'}, }, ); // "507f191e810c19729de860ea" print(result mutateddocumentids first); supplying string ids w hen creating a document, you can assign it a custom id this custom id can be generated using a single string value or a combination of two or more string values this flexibility in structuring document identifiers allows you to customize document ids to your specific requirements, use cases, or standard naming conventions the following snippet demonstrates a new document assigned the custom id "123" let result = await ditto store execute( query "insert into cars documents (\ newcar)", arguments \[ newcar \[ " id" "123", "color" "blue"] ]); // "123" print(result mutateddocumentids()\[0])var result = ditto store execute( "insert into cars documents (\ newcar)", mapof("newcar" to mapof(" id" to "123", "color" to "blue"))) // "507f191e810c19729de860ea" println(result mutateddocumentids() first())const newcar = { id "123", color "blue" } const result = await ditto store execute(` insert into cars documents (\ newcar)`, { newcar } ); // "123" console log(result mutateddocumentids()\[0] value)map\<string, string> newcar = new hashmap<>(); newcar put(" id", "123"); newcar put("color", "blue"); dittoqueryresult result = (dittoqueryresult) ditto store execute( "insert into cars documents (\ newcar)", collections singletonmap("newcar", newcar), new continuation<>() { @nonnull @override public coroutinecontext getcontext() { return emptycoroutinecontext instance; } @override public void resumewith(@nonnull object o) { if (o instanceof result failure) { // handle failure } } } ); // "123" system out println(result mutateddocumentids()\[0]);var insertargs = new dictionary\<string, object>(); insertargs add("newcar", new { id = "123", color = "blue" }); var result = await ditto store executeasync( "insert into your collection name documents (\ newcar)", insertargs); // "123" result mutateddocumentids foreach(id => console writeline(id));std map\<std string, std map\<std string, std string>> args; args\["newcar"] = {{" id", "123"},{"color", "blue"}}; auto result = ditto get store() execute( "insert into cars documents (\ newcar)", args); // "123" std cout << result mutated document ids()\[0] to string();let query result = ditto store() execute( "insert into cars documents (\ newcar)", some(serde json json!({ "newcar" { " id" "123", "color" "blue" } }) into()), ) await?; // "123" println!("{}", query result mutated document ids()\[0] to string())final result = await ditto store execute( "insert into cars documents (\ newcar)", arguments { "newcar" {" id" "123","color" 'blue'}, }, ); // "123" print(result mutateddocumentids first); following is the new 123 document that results ditto document { " id" "123", "color" "blue" } forming composite keys the following demonstrates combining the vin and make fields to form the composite key let arguments = \[ newcar \[ " id" \[vin "123", make "toyota"], "color" "blue"] ]; let result = await ditto store execute( query "insert into cars documents (\ newcar)", arguments arguments); // "{vin "123", make "toyota"}" print(result mutateddocumentids()\[0])var result = ditto store execute( "insert into cars documents (\ newcar)", mapof( "newcar" to mapof( " id" to mapof( "vin" to "123", "make" to "toyota" ), "color" to "blue" ))) // "{vin "123", make "toyota"}" println(result mutateddocumentids() first())const newcar = { id { vin "123", make "toyota" }, color "blue" } const result = await ditto store execute(` insert into cars documents (\ newcar)`, { newcar }); // { vin "123", make "toyota" } console log(result mutateddocumentids()\[0] value)map\<string, string> newcarid = new hashmap<>(); newcarid put("vin", "123"); newcarid put("make", "toyota"); map\<string, object> newcar = new hashmap<>(); newcar put(" id", newcarid); newcar put("color", "blue"); dittoqueryresult result = (dittoqueryresult) ditto store execute( "insert into cars documents (\ newcar)", collections singletonmap("newcar", newcar), new continuation<>() { @nonnull @override public coroutinecontext getcontext() { return emptycoroutinecontext instance; } @override public void resumewith(@nonnull object o) { if (o instanceof result failure) { // handle failure } } } ); // "{vin "123", make "toyota"}" system out println(result mutateddocumentids()\[0]);var newid = new { vin "123", make "toyota"}; var insertargs = new dictionary\<string, object>(); insertargs add("newcar", new { id = newid, color = "blue" }); var result = await ditto store executeasync( "insert into your collection name documents (\ newcar)", insertargs); // "{vin "123", make "toyota"}" result mutateddocumentids foreach(id => console writeline( system text json jsonserializer serialize(id)));struct carid { std string vin; std string make; }; struct car { carid id; std string color; }; std map\<std string, car> args; args\["newcar"] = {{"123", "toyota"}, "blue"}; auto result = ditto get store() execute( "insert into cars documents (\ newcar)", args); // "{vin "123", make "toyota"}" std cout << result mutated document ids()\[0] to string();let query result = ditto store() execute( "insert into cars documents (\ newcar)", some(serde json json!({ "newcar" { " id" { "vin" "123", "make" "toyota" }, "color" "blue" } }) into()), ) await?; // "{vin "123", make "toyota"}" println!("{}", query result mutated document ids()\[0] to string())final result = await ditto store execute( "insert into cars documents (\ newcar)", arguments { "newcar" { " id" {"vin" "123", "make" "toyota"}, "color" 'blue' }, }, ); // "{vin "123", make "toyota"}" print(result mutateddocumentids first); creating attachments there are two separate steps in the process of creating an attachment create the attachment in the ditto store ( /#initiating attachment objects ) reference the returned attachment token in a document ( /#referencing attachment tokens for a realworld usage scenario, see either the demo chat app for ios or android in the getditto > https //github com/getditto/demoapp chat/tree/main github repository initiating attachment objects to create the attachment object that encodes the actual contents of the file to store externally, call the newattachment method on the store namespace when creating an attachment when creating an attachment, provide a valid path to the large file or deeply embedded document you want to encode as an attachment failure to do so may result in errors related to input output (io) operations storing an attachment in the local ditto store (instead of externally) is currently only available in the ditto sdk for javascript to use a dql type other than a register — the default data type in ditto — you must explicitly specify the type in your query; otherwise, ditto defaults to the register type as follows if desired, enclose extra information about the attachment, such as name and description this metadata is useful for attachment fetching operations let newattachment = try await ditto store newattachment(path filepath)val attachment = runblocking { ditto store newattachment(attachmentpathorinputstream, attachmentmetadata) }const newattachment = await ditto store newattachment(filepathordata)try (dittoattachment attachment = ditto store newattachment(attachmentpathorinputstream, attachmentmetadata)) {var newattachment = await ditto store newattachmentasync(path filepath);auto attachment = ditto get store() new attachment("/path/to/my/file pdf");use dittolive ditto prelude ; use serde json json; use std {collections hashmap, path path}; use serde serialize; async fn attachment doc snippet( peer a \&ditto, peer b \&ditto, filepath \&path, ) > result<(), error> { // creating an attachment in the local ditto store from a file let new attachment = peer a store() new attachment(filepath, < > default()) await?;final newattachment = await ditto store newattachment(filepathordata); adding optional metadata if you want to include information about the attachment, such as the attachment filename, as shown in the following snippet, a description, and other relevant details, enclose it in a metadata object as key value pairs let metadata = \["name" "name of file"] let newattachmentwithmetadata = try await ditto store newattachment(path filepath, metadata metadata)val attachmentmetadata = mapof("name" to attachmentfilename) val attachment = runblocking { ditto store newattachment(attachmentpathorinputstream, attachmentmetadata) }const metadata = { name 'image png' } const newattachment = await ditto store newattachment(imagebytes, metadata)val attachmentmetadata = mapof("name" to attachmentfilename) val attachment = runblocking { ditto store newattachment(attachmentpathorinputstream, attachmentmetadata) }var metadata = new dictionary\<string, string>() { { "name", "image png" } }; var newattachmentwithmetadata = await ditto store newattachmentasync(filepath, metadata);auto attachment = ditto get store() new attachment("/path/to/my/file pdf", { {"name", "name of file"} });let user data = hashmap from iter(\[ ("name" into(), "image png" into()), // idea attach a small "summary" of the file contents to preview them in // the ui so that the user has some idea of what to "download"/ fetch // // for example // for a text file, include a title or the first word of the filename // for an image, include a base64 encoded thumbnail, as follows ( "thumbnail" into(), "/9j/4atg9y zw0ga x bzd w0g zg9sb " into(), ), ]);// coming soon for example, in the following snippet, the metadata property encapsulates the name of the attachment, as well as its description val attachmentmetadata = mapof( "name" to "japan png", "description" to "this is an image of a sunset in japan " ) val attachment = runblocking { ditto store newattachment(attachmentpathorinputstream, attachmentmetadata) }val attachmentmetadata = mapof( "name" to "japan png", "description" to "this is an image of a sunset in japan " ) val attachment = runblocking { ditto store newattachment(attachmentpathorinputstream, attachmentmetadata) }const metadata = { name 'japan png', description 'this is an image of a sunset in japan ' } const newattachment = await ditto store newattachment(imagebytes, metadata)val attachmentmetadata = mapof( "name" to "japan png", "description" to "this is an image of a sunset in japan " ) val attachment = runblocking { ditto store newattachment(attachmentpathorinputstream, attachmentmetadata) }var metadata = new dictionary\<string, string>() { { "name", "japan png" }, { "description", "this is an image of a sunset in japan " } }; var newattachmentwithmetadata = await ditto store newattachmentasync(filepath, metadata);auto attachment = ditto get store() new attachment("/path/to/my/file pdf", { {"name", "japan png"}, {"description", "this is an image of a sunset in japan "} });let user data = hashmap from iter(\[ ("name" into(), "japan png" into()), ( "thumbnail" into(), "/9j/4atg9y zw0ga x bzd w0g zg9sb " into(), ), ( "description" into(), "this is an image of a sunset in japan " into() ), ]); let new attachment with metadata = peer a store() new attachment(filepath, user data) await?;// coming soon referencing attachment tokens after creating and storing a new attachment object in ditto, you receive an attachment token as part of the response an attachment token is an attachment token is a pointer that references its associated attachment object this token is how you interact with the attachment, such as when fetching or linking it with a document t he following snippet demonstrates how to create a new document object containing a new attachment, and then insert it into the cars collection // create a new document object and store the attachment on the `my attachment` field let newdocument \[string any] = \[" id" "123", "my attachment" newattachment] // insert the new document into the collection // note that the `my attachment` field needs to be declared as an `attachment` data type try await ditto store execute( query """ insert into collection cars (my attachment attachment) documents (\ newdocument) """, arguments \["newdocument" newdocument] )// create a new document object and store the attachment on the `my attachment` field val document = mapof("some" to "string", "my attachment" to attachment) val insertquery = "insert into collection cars (my attachment attachment) documents (\ document)" // insert the new document into the collection // note that the `my attachment` field needs to be declared as an `attachment` data type val insertquery = "insert into collection cars (my attachment attachment) documents (\ document)" val insertarguments = mapof("document" to document) val insertqueryresult = runblocking { ditto store execute(insertquery, insertarguments) }// create a new document object and store the attachment on the `my attachment` field const newdocument = { id "123", my attachment newattachment } // insert the new document into the collection // note that the `my attachment` field needs to be defined as an attachment data type await ditto store execute(` insert into collection cars (my attachment attachment) documents (\ newdocument)`, { newdocument } );// create a new document object and store the attachment on the `my attachment` field val document = mapof("some" to "string", "my attachment" to attachment) val insertquery = "insert into collection cars (my attachment attachment) documents (\ document)" // insert the new document into the collection // note that the `my attachment` field needs to be declared as an `attachment` data type val insertquery = "insert into collection cars (my attachment attachment) documents (\ document)" val insertarguments = mapof("document" to document) val insertqueryresult = runblocking { ditto store execute(insertquery, insertarguments) }// creating a ditto document with an attachment // create a new document object and store the attachment on the `my attachment` field var newdocument = new dictionary\<string, object>() { { " id", "123" }, { "my attachment", newattachment } }; // insert the new document into the collection // note that the `my attachment` field needs to be declared as an `attachment` data type await ditto store executeasync( query @" insert into collection cars (my attachment attachment) documents (\ newdocument) ", arguments new dictionary\<string, object>() { { "newdocument", newdocument } } );// insert a new document into the collection // note that the `my attachment` field needs to be declared as an `attachment` data type let query result = peer a store() execute( "insert into collection cars (my attachment attachment) \\ documents (\ new document)", some(serde json json!({ "new document" { " id" "123", "my attachment" new attachment }, }) into()), ) await?;// coming soon creating maps there are two ways to create a map structure within a document in an insert operation — create a new document and nest it with this set of fields in an update operation — if the map does not exist, create it (see docid\ ys sagdx2wn1tcodagusj ) to represent a highly complex data structure in a map , consider embedding it with an additional map embedding a map within a map establishes an additional hierarchy the decision to use deeply embedded maps in a single document or opt for a flat model depends on your requirements, relationships between data, and tolerance for certain tradeoffs the flat model is a simple, non‑embedded structure in which you spread your data across multiple, separate documents inserting to create a map when inserting a new document in ditto, you can define a field as a map and include the structure of key value pairs nested within it — a two in one approach for example let arguments \[string any] = \[ "newcar" \[ " id" "123", "properties" \[ "color" "blue", "mileage" 3000 ] } ]; await ditto store execute( query "insert into collection cars (properties map) documents (\ newcar)", arguments arguments);val arguments = mapof( "newcar" to mapof( " id" to "123", "properties" to mapof( "color" to "blue", "mileage" to 3000 ) ) ) ) ditto store execute(""" insert into collection cars (properties map) documents (\ newcar) """, arguments)const newcar = { id "123", properties { color 'blue', mileage 3000 } } await ditto store execute(` insert into collection cars (properties map) documents (\ newcar)`, { newcar } );map\<string, object> properties = new hashmap<>(); properties put("color", "blue"); properties put("mileage", 3000); map\<string, object> newcar = new hashmap<>(); newcar put(" id", "123"); newcar put("properties", properties); dittoqueryresult result = (dittoqueryresult) ditto store execute( "insert into collection cars (properties map) documents (\ newcar)", collections singletonmap("newcar", newcar), new continuation<>() { @nonnull @override public coroutinecontext getcontext() { return emptycoroutinecontext instance; } @override public void resumewith(@nonnull object o) { if (o instanceof result failure) { // handle failure } } } );var submap = new { color = "blue", mileage = 3000 }; var insertargs = new dictionary\<string, object>(); insertargs add("newcar", new { id = newid, properties = submap }) var result = await ditto store executeasync( "insert into collection cars (properties map) documents (\ newcar)", insertargs);struct properties { std string color; int mileage; }; struct car { std string id; properties properties; }; // std map\<std string, car> args; args\["newcar"] = {"123", {"blue", 3000}}; ditto get store() execute( "insert into collection your collection name (properties map)" \+ " documents (\ newcar)", args);let query result = ditto store() execute( "insert into collection cars (properties map) documents (\ newcar)", some(serde json json!({ "newcar" { " id" "123", "properties" { "color" "blue", "mileage" 3000 } } }) into()) ) await?;final newcar = { " id" "123", "properties" { "color" 'blue', "mileage" 3000, }, }; await ditto store execute(""" insert into collection cars (properties map) documents (\ newcar)""", arguments {"newcar" newcar}, ); another method to creating a map within a document is to perform an update operation in the update approach, you set the structure of key value pairs and specify the document id for storage for example, this statement creates the map structure — unless it already exists — setting a single key value pair of color is red within the properties map for the document with the id 123 in the cars collection dql update collection cars (properties map) set properties > ( color = 'red' ) where id = '123'