The table properties dialog has an optional ID field. An ID you enter here will be exported as the <table> tag ID attribute in HTML-based output formats. You will not need this for normal tables but it is sometimes useful. For example, when you use the sortable tables option in the Help & Manual
Premium Pack you need to enter a special ID here to identify your table as sortable.
You may also need to use IDs in tables if you are planning to manipulate your tables with your own CSS or JavaScript code.
In HTML an ID always has to be unique, you should never have more than one object on the same page with the same ID. This can be a problem if you are cloning copies of a ready-made table, for example from snippets – if the table already contains an ID you need to edit it every time you insert a copy and if it doesn't you need to remember to add one. You can get around this by creating an automatically-incrementing ID with text variables.
You can't mix text and variables in topic IDs so you need to create two variables to do this.
1.Go to Project Explorer > Configuration > Common Properties > Text Variables and create two text variables, one for the static part of the ID and one for the incrementing number. The static part can have any name you like, the incrementing number must have two plus characters at the end of its name, for example TABLENO++.
2.Let's say the two variables are TABLEID and TABLENO++. Now enter any text you like as the text for the TABLEID variable, for example table_, and a 0 (the number zero) as the text for the TABLENO++ variable, like this:

3. Then instead of an ID, type in both variables in the Table ID: field in your table properties, like this:
<%TABLEID%><%TABLENO++%>
Then every time you make a copy of the table in your project a new unique ID will be generated automatically. The first will be table_1, the second will be table_2 and so on.