I'm running a PostgreSQL query:
'SELECT * FROM table'
On my server side, I'm trying to generate a JSON object of the below format, but some of the column# values are set to 'undefined' because the row.value# is undefined:
{
column1: row.value1,
column2: row.value2,
column3: row.value3,
column4: row.value4,
column5: row.value5,
column6: row.value6,
column7: row.value7,
column8: row.value8,
column9: row.value9,
}
On my client side, I'm trying to receive a set of JSON objects, but they don't have the same format because whenever one of the column#'s has a value of undefined, it's removed from the JSON object so that it looks like the below (because column5, column6, and column8 were undefined).
{
column1: row.value1,
column2: row.value2,
column3: row.value3,
column4: row.value4,
column7: row.value7,
column9: row.value9,
}
My solution was to give the properties in the JSON object a default value in case of the row.value# being undefined. How can I do this (replace 'undefined' with some default value in the object).
You can use a ternary operator (? :) like this:
const row = {
value2: "Praveen",
value6: "Kumar",
value8: "Purushothaman"
};
console.log({
column1: row.value1 ? row.value1 : "NA",
column2: row.value2 ? row.value2 : "NA",
column3: row.value3 ? row.value3 : "NA",
column4: row.value4 ? row.value4 : "NA",
column5: row.value5 ? row.value5 : "NA",
column6: row.value6 ? row.value6 : "NA",
column7: row.value7 ? row.value7 : "NA",
column8: row.value8 ? row.value8 : "NA",
column9: row.value9 ? row.value9 : "NA",
});This gives me an output of:
{
"column1": "NA",
"column2": "Praveen",
"column3": "NA",
"column4": "NA",
"column5": "NA",
"column6": "Kumar",
"column7": "NA",
"column8": "Purushothaman",
"column9": "NA"
}
There is a way to use null coalescing operator too. But that might not be supported always. However, the above logic works every time.
You can do something like this
const defaultValues = {
col1: "col1",
col2: "col2",
col3: "col3"
};
const fromApi = {
col2 : 'my value col2'
}
const result = {...defaultValues, ...fromApi}
console.log(result)