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i want to send unique records for every user who logs in from a mysql database

i want to send every user who logs in a list of unique records i.e not same records from the database,
for every user i want to skip the records that have already been sent to other signed users.bare with me ,am a beginner,how can i implement such?
here is the code that fetches the records from the database
phrases.findAll({
where: {
userId: user.id,
phraseStatus: 1
},
limit: 10,
offset,
10
})
.then((data) => {
userObj.phrases.push(...data);
return res.status(200).json(userObj);
});

You will need to keep track of what has been sent to other users. I suggest you keep a table like phrases_sent to record what has been sent so far. Add the phrase_id to this new table so you have a relationship.
Take a look at associations in the docs.
You can then query the phrases table by outer joining to your phrases_sent table to return phrases that have not been sent so far.
Something like:
const phrases = await sequelize.models.phrase.findAll({
where: {
'$phrasesSents.phrase_id$': {[Op.is]: null} // query the joined table
},
attributes: ['phrase.phrase'], // the unused phrases
include: [
{
attributes: [],
model: sequelize.models.phrasesSent,
required: false, // specify this is a left outer join
}
],
raw: true,
nest: true
});
Would yield:
SELECT "phrase"."phrase"
FROM "phrases" AS "phrase"
LEFT OUTER JOIN "phrases_sent" AS "phrasesSents" ON "phrase"."id" = "phrasesSents"."phrase_id"
WHERE "phrasesSents"."phrase_id" IS NULL;
I believe doing a LEFT OUTER JOIN has performance benefits over a NOT IN (SELECT ...) style query.

Sequelize wrap column with " in where condition

I have a JSONB column in DB.
I'd like to have request to DB where I can check if some value in this JSON it true or false:
SELECT *
FROM table
WHERE ("json_column"->'data'->>'data2')::boolean = true AND id = '00000000-1111-2222-3333-456789abcdef'
LIMIT 1
So, my sequelize request:
const someVariableWithColumnName = 'data2';
Model.findOne({
where: {
[`$("json_column"->'data'->>'${someVariableWithColumnName}')::boolean$`]: true,
id: someIdVariable,
},
order: [/* some order, doesn't matter */],
})
And sequelize generate bad result like:
SELECT *
FROM table
WHERE "(json_column"."->'data'->>'data2')::boolean" = true AND id = '00000000-1111-2222-3333-456789abcdef'
LIMIT 1
Split my column by . and add " to every element.
Any idea how to get rid of adding " to the column in where condition?
Edit:
Here is my query with sequelize.literal():
const someVariableWithColumnName = 'data2';
Model.findOne({
where: {
[sequelize.literal(`$("json_column"->'data'->>'${someVariableWithColumnName}')::boolean$`)]: true,
id: someIdVariable,
},
order: [/* some order, doesn't matter */],
})

You can use Sequelize.literal() to avoid spurious quotes. IMHO, wrapping the json handling in a db function might also be helpful.

I just came across a similar use case.
I believe you can use the static sequelize.where method in combination with sequelize.literal.
Here is the corresponding documentation in sequelize API reference: https://sequelize.org/master/class/lib/sequelize.js~Sequelize.html#static-method-where
And here is an example (although I will admit hard to find) in the regular documentation:
https://sequelize.org/master/manual/model-querying-basics.html#advanced-queries-with-functions--not-just-columns-
In the end for your specific sit try something like this:
const someVariableWithColumnName = 'data2';
Model.findOne({
where: {
[Op.and]: [
// We provide the virtual column sql as the first argument of sequelize.where with sequelize.literal.
// We provide the matching condition as the second argument of sequelize.where, with the usual sequelize syntax.
sequelize.where(sequelize.literal(`$("json_column"->'data'->>'${someVariableWithColumnName}')::boolean$`), { [Op.eq]: true }),
{ id: someIdVariable }
]
})

How to get all data of table by use of sequelize

I have postgres table name tests which contain few records, now I want to fetch all record of this table but unable because its provides only id,createdAt and updatedAt.
So either I have to provide an object which contain column name that I don't want, I wish it should be dynamic so after this if I pass another table name it will provide data of that.
I tried this but it returns null array of object
Project.findAll(attributes: ['*']
}).then(function(project) {
console.log("select_data: " + JSON.stringify(project));
})

I'm not totally clear on what the question / problem is here, but it sounds like when you're defining your model, you might not have included all the column names of the table in your model definition. Here's what it should look like:
module.exports = function(sequelize, DataTypes) {
const test = sequelize.define('test', {
my_column: DataTypes.STRING,
my_other_column: DataTypes.STRING,
my_boolean_column: DataTypes.BOOLEAN,
}, {
timestamps: true,
underscored: true,
tableName: 'tests',
})
return test
}
Notice each column of the table is explicitly defined in the model.

Create a text index on MongoDB schema which references another schema

I am trying to add an index to a certain Schema with mongoose for text searches. If I add a text index to individual fields it works fine, also with compound indexes it is okay. For example the answer provided here is great:
Full text search with weight in mongoose
However, I am trying to add an index to fields which are references to other Schemas. For example my model looks like the following:
var Book = new Schema({
"title": String,
"createdAt": Date,
"publisher": {
"type": Schema.ObjectId,
"ref": "Publisher"
},
"author": {
"type": Schema.ObjectId,
"ref": "Author"
},
"isbn": String
});
So something like the following indexing doesn't work when you perform a search query as described below:
Indexing:
Book.index({"title": "text", "publisher.name": "text", "author.firstName": "text"});
Search query:
function searchBooks(req, res) {
var query = req.query.searchQuery;
Book.find({ $text: { $search: query } })
.populate('author publisher')
.limit(25)
.exec(function(err, books) {
if (err) {
res.json(err);
} else {
res.json(books);
}
}
);
}
Does anyone have any suggestions of how to add a text index in for the "publisher" and "author" fields, I am using the "populate" mongodb method to pull in the data for these schemas.

I think, what you are looking for is the ability to join tables of data and perform a query against the sum of that data. That is something you need a relational database for, which MongoDB isn't.
So I recommend you change your approach in how you would like to preform your search, e.g. search for your keyword within both author and title instead of attempting to search the whole dataset at the same time.

Sequelize Many to Many - How to create a new record and update join table

I'm building a simple database with node, express and sequelize. I have created my models, and sequelize created the tables in my database.
I have the models User and City, with a many to many relationship. Sequelize created the tables Users, Cities and a join table CitiesUsers: with UserId and CityId.
My question is when I create a new user how do I update that join table? The CityId property gets ignored on create.
//Models use
//City.hasMany(User);
//User.hasMany(City);
var user = User.build({
first_name: 'John',
last_name: 'Doe',
CityId: 5
});
user.save();

After digging further into the documentation, I believe I've found the answer.
When creating a many to many relationship sequelize creates get, set and add methods to each model.
From the docs assuming models User and Project with many to many:
http://docs.sequelizejs.com/en/latest/docs/associations/#belongs-to-many-associations
This will add methods getUsers, setUsers, addUsers to Project, and
getProjects, setProjects and addProject to User.
So in my case I did the following where "city" is a specific City model returned from City.find...
//user.setCities([city]);
models.User.find({ where: {first_name: 'john'} }).on('success', function(user) {
models.City.find({where: {id: 10}}).on('success', function(city){
user.setCities([city]);
});
});

You can create a new instance of the model used as the join table once both City and User models have been created.
const User = sequelize.define('user')
const City = sequelize.define('city')
const UserCity = sequelize.define('user_city')
User.belongsToMany(City, { through: UserCity })
City.belongsToMany(User, { through: UserCity })
const user = await User.create()
const city = await City.create()
const userCity = await UserCity.create({
userId: user.userId,
cityId: city.cityId,
})

Just to add on to the many excellent answers in this thread, I find generally that when I have one entity referencing another, I want to create the referenced entity if (and only if) it does not already exist. For this I like to use findOrCreate().
So imagine you were storing articles, and each article could have any number of tags. What you'd typically want to do is:
Iterate through all the desired tags, and check if they exist. Create them if they don't already exist.
Once all the tags have been found or created, create your article.
Once your article has been created, link it to the tags you looked up (or created) in step 1.
For me, this winds up looking like:
const { article, tags } = model.import("./model/article");
let tagging = [
tags.findOrCreate({where: {title: "big"}}),
tags.findOrCreate({where: {title: "small"}}),
tags.findOrCreate({where: {title: "medium"}}),
tags.findOrCreate({where: {title: "xsmall"}})
];
Promise.all(tagging).then((articleTags)=> {
article.create({
title: "Foo",
body: "Bar"
}).then((articleInstance) => {
articleInstance.setTags(articleTags.map((articleTag) => articleTag[0]));
})
})

From The docs v3:
// Either by adding a property with the name of the join table model to the object, before creating the association
project.UserProjects = {
status: 'active'
}
u.addProject(project)
// Or by providing a second argument when adding the association, containing the data that should go in the join table
u.addProject(project, { status: 'active' })
// When associating multiple objects, you can combine the two options above. In this case the second argument
// will be treated as a defaults object, that will be used if no data is provided
project1.UserProjects = {
status: 'inactive'
}
u.setProjects([project1, project2], { status: 'active' })
// The code above will record inactive for project one, and active for project two in the join table