How to write tags, can give a thought?

tags, just like the SF each question below the label function, is how to write?
Whether to add tags every time, and then in the Database Tags table query, do not add? Can you give me a definite idea?

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tags, just like the SF each question below the label function, is how to write?
Whether to add tags every time, and then in the Database Tags table query, do not add? Can you give me a definite idea?

Queries placed in the search engine, with "," do participle

Build a tag table tags, fields have ID and name to build a label relationship table articletag, field articleID and tag_id

Add tags when the query tags table, if already exist to get tagID, if not add a new tag and get tagID finally put the relationship between the article and the label Article_tag table can be.

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