How to Select through KNEX ORM

Select is the only command available in the whole SQL to retrieve data. KNEX provides an implementation of the "Select" Query. The following code illustrates:

knex.select("*").from("depts")
.then(function (dept) {
dept.forEach(function(value){
console.log(value.deptno);
});
}).catch(function(err) {
// All the error can be checked in this piece of code
console.log(err);
}).finally(function() {
// To close the connection pool
knex.destroy();
});
}

The above code has following important observations:

a. Its Selecting data from a table named "Depts". We are selecting all the columns and rows.
b. Once select query has fetched rows, it will run a promise of .then
c. "dept" in the .then function is a collection of all records fetched from the table.
d. We can access individual columns like "value.deptno", "value.dname" within forEach loop.

Happy Coding !!!

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Rohit Dhand

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