Insert multiple values into a column of a table in PostgreSQL [duplicate] - node.js

Question

A single row can be inserted like this:
client.query("insert into tableName (name, email) values ($1, $2) ", ['john', 'john#gmail.com'], callBack)
This approach automatically comments out any special characters.
How do i insert multiple rows at once?
I need to implement this:
"insert into tableName (name, email) values ('john', 'john#gmail.com'), ('jane', 'jane#gmail.com')"
I can just use js string operators to compile such rows manually, but then i need to add special characters escape somehow.

Answer 1

Use pg-format like below.
var format = require('pg-format');
var values = [
[7, 'john22', 'john22#gmail.com', '9999999922'],
[6, 'testvk', 'testvk#gmail.com', '88888888888']
];
client.query(format('INSERT INTO users (id, name, email, phone) VALUES %L', values),[], (err, result)=>{
console.log(err);
console.log(result);
});

Answer 2

One other way using PostgreSQL json functions:
client.query('INSERT INTO table (columns) ' +
'SELECT m.* FROM json_populate_recordset(null::your_custom_type, $1) AS m',
[JSON.stringify(your_json_object_array)], function(err, result) {
if (err) {
console.log(err);
} else {
console.log(result);
}
});

Answer 3

Following this article: Performance Boost from pg-promise library, and its suggested approach:
// Concatenates an array of objects or arrays of values, according to the template,
// to use with insert queries. Can be used either as a class type or as a function.
//
// template = formatting template string
// data = array of either objects or arrays of values
function Inserts(template, data) {
if (!(this instanceof Inserts)) {
return new Inserts(template, data);
}
this.rawType = true;
this.toPostgres = function () {
return data.map(d=>'(' + pgp.as.format(template, d) + ')').join(',');
};
}
An example of using it, exactly as in your case:
var users = [['John', 23], ['Mike', 30], ['David', 18]];
db.none('INSERT INTO Users(name, age) VALUES $1', Inserts('$1, $2', users))
.then(data=> {
// OK, all records have been inserted
})
.catch(error=> {
// Error, no records inserted
});
And it will work with an array of objects as well:
var users = [{name: 'John', age: 23}, {name: 'Mike', age: 30}, {name: 'David', age: 18}];
db.none('INSERT INTO Users(name, age) VALUES $1', Inserts('${name}, ${age}', users))
.then(data=> {
// OK, all records have been inserted
})
.catch(error=> {
// Error, no records inserted
});
UPDATE-1
For a high-performance approach via a single INSERT query see Multi-row insert with pg-promise.
UPDATE-2
The information here is quite old now, see the latest syntax for Custom Type Formatting. What used to be _rawDBType is now rawType, and formatDBType was renamed into toPostgres.

Answer 4

You are going to have to generate the query dynamically. Although possible, this is risky, and could easily lead to SQL Injection vulnerabilities if you do it wrong. It's also easy to end up with off by one errors between the index of your parameters in the query and the parameters you're passing in.
That being said, here is an example of how you could do write this, assuming you have an array of users that looks like {name: string, email: string}:
client.query(
`INSERT INTO table_name (name, email) VALUES ${users.map(() => `(?, ?)`).join(',')}`,
users.reduce((params, u) => params.concat([u.name, u.email]), []),
callBack,
)
An alternative approach, is to use a library like #databases/pg (which I wrote):
await db.query(sql`
INSERT INTO table_name (name, email)
VALUES ${sql.join(users.map(u => sql`(${u.name}, ${u.email})`), ',')}
`)
#databases requires the query to be tagged with sql and uses that to ensure any user data you pass is always automatically escaped. This also lets you write the parameters inline, which I think makes the code much more readable.

Answer 5

Using npm module postgres (porsager/postgres) which has Tagged Template Strings at the core:
https://github.com/porsager/postgres#multiple-inserts-in-one-query
const users = [{
name: 'Murray',
age: 68,
garbage: 'ignore'
},
{
name: 'Walter',
age: 80,
garbage: 'ignore'
}]
sql`insert into users ${ sql(users, 'name', 'age') }`
// Is translated to:
insert into users ("name", "age") values ($1, $2), ($3, $4)
// Here you can also omit column names which will use all object keys as columns
sql`insert into users ${ sql(users) }`
// Which results in:
insert into users ("name", "age", "garbage") values ($1, $2, $3), ($4, $5, $6)
Just thought I'd post since it's like brand new out of beta and I've found it to be a better philosophy of SQL library. I think would be preferable over the other postgres/node libraries posted in other answers. IMHO

Answer 6

Hi I know I am late to the party, but what worked for me was a simple map.
I hope this will help someone seeking for same
let sampleQuery = array.map(myRow =>
`('${myRow.column_a}','${myRow.column_b}') `
)
let res = await pool.query(`INSERT INTO public.table(column_a, column_b) VALUES ${sampleQuery} `)

Answer 7

client.query("insert into tableName (name, email) values ($1, $2),($3, $4) ", ['john', 'john#gmail.com','john', 'john#gmail.com'], callBack)
doesn't help?
Futher more, you can manually generate a string for query:
insert into tableName (name, email) values (" +var1 + "," + var2 + "),(" +var3 + ", " +var4+ ") "
if you read here, https://github.com/brianc/node-postgres/issues/530 , you can see the same implementation.