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Replies for: Hi Julia, Can you please help me,How can we write query for WHERE IN, when passing array to query it is giving no records found 404 response when a...

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juliest88 profile image
Julia Strichash •

Hi,
You need to use the prepared statement.
Just put placeholders (?) in the IN => IN(?, ?)
and pass the [5,6] array as a parameter to the query async method:

const result = await query(sql, [5, 6]);
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In my repository(on GitHub), I added an additional function in the common.utils.js file. this function sets the placeholders(?) instead of the array items, and returns back a string like '?, ?'.

exports.getPlaceholderStringForArray = (arr) => {
    if (!Array.isArray(arr)) {
        throw new Error('Invalid input');
    }

    // if is array, we'll clone the arr 
    // and fill the new array with placeholders
    const placeholders = [...arr];
    return placeholders.fill('?').join(', ').trim();
}
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So you can use this function to fill the placeholders as the number of your array something like => IN(getPlaceholderStringForArray([5, 6]))
Just don't forget to import the function.

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ramakanthrapaka profile image
RamakanthRapaka • • Edited

Hi Julie,

var farmercropsLists = await UserCropsModel.findCropsByChampsArray({ 'farmer.id': farmar_ids });

if (!Object.keys(params).length) {
return await query(sql);
}
for (const [key, value] of Object.entries(params)) {
var values = value;
sql += WHERE ${key} IN ( + getPlaceholderStringForArray(value) + );
}
console.log(sql);

    return await query(sql, values);
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can you please suggest JULIE how can we use where and where IN in single function

Thank you