timw4mail/node-query

/**
 * Driver for SQLite databases
 *
 * @module drivers/Sqlite
 */
module.exports = (() => {
    delete require.cache[require.resolve('../Driver')];
    const driver = require('../Driver');

    // Sqlite doesn't have a truncate command
    driver.hasTruncate = false;

    /**
     * SQL to insert a group of rows
     * Override default to have better compatibility
     *
     * @param {String} table - The table to insert to
     * @param {Array} [data] - The array of object containing data to insert
     * @return {String} - The generated sql statement
     */
    driver.insertBatch = (table, data) => {
        // Get the data values to insert, so they can
        // be parameterized
        let sql = '';
        const first = data.shift();

        const vals = [];
        data.forEach(obj => {
            const row = [];
            Object.keys(obj).forEach(key => {
                row.push(obj[key]);
            });
            vals.push(row);
        });

        sql += `INSERT INTO ${driver.quoteTable(table)}\n`;

        // Get the field names from the keys of the first
        // object to be inserted
        const fields = Object.keys(first);
        const cols = [];
        fields.forEach(key => {
            cols.push(`'${driver._quote(first[key])}' AS ${driver.quoteIdentifiers(key)}`);
        });

        sql += `SELECT ${cols.join(', ')}\n`;

        vals.forEach(rowValues => {
            const quoted = rowValues.map(value => String(value).replace('\'', '\'\''));
            sql += `UNION ALL SELECT '${quoted.join('\', \'')}'\n`;
        });

        return {
            sql: sql,
            values: undefined
        };
    };

    return driver;
})();