Comment 2 for bug 1411541

right now, metric_query_table contains fields for error text, explain and query text.
It limits the max length of these fields.

what we need to do is to add another repos table that can store large strings
by chunking them into multiple rows using id, seqNum. Metric_query_table will
contain an id that can be used to read and write from/into this new repos table.

This will be similar to metadata TEXT table which is used to store constraints,
views, etc, of arbitrary length and are pointed to by an id from the original metadata table.

If query text can fit in the predefined fields, then we will store it inlined. If it exceeds
that length, then it will be stored in REPOS_TEXT table and a identifier will be stored
in metric_query_table.

We should not store truncated information for query text or explain otherwise one
will not be able to use it correctly at a later time.