正确的MariaDB语法用于SQL替换语句

Question

After trying to determine why my SQL statement was returning an error in the Node code I am refactoring to connect to MariaDB rather than via SQL Anywhere, I have narrowed it down to the REPLACE statement we use to compute how many records to process, and how many to skip.

My initial test SQL SELECT statement looks like this:

SELECT customer_name FROM ar.customers

We then use a REPLACE statement to, as I say, determine how many records to process, and how many to skip. When we were using SQL Anywhere that looked like this:

const sql = this.query.replace(/SELECT/i, `SELECT TOP ${recordsPerRun} START AT ${recordsProcessed + 1}`);

That syntax needs to change because MariaDB uses "LIMIT" instead of "TOP". And from my understanding, the first parameter will be the number of records to skip, and the second one how many to return.

So, in my case, it'd be something like:

LIMIT ${recordsProcessed}, ${recordsPerRun}

However, I can't quite get the full syntax right. How can I write this REPLACE statement in a way that will work with my initial test SQL SELECT statement from above? This seems tricky to do since in MariaDB LIMIT now goes at the end of the query, not at the beginning, like TOP did for MySQL.

Answer 1

LIMIT goes at the end, so there's nothing to replace, just concatenate it:

const sql = this.query + ` LIMIT ${recordsProcessed}, ${recordsPerRun}`;

or combine it into the template:

const sql = `${this.query} LIMIT ${recordsProcessed}, ${recordsPerRun}`;