modify primer.md to have exactly the same contents as the one in up-to-date master branch
diff --git a/asterix-doc/src/site/markdown/aql/primer.md b/asterix-doc/src/site/markdown/aql/primer.md
index dee6b93..fc8ea9a 100644
--- a/asterix-doc/src/site/markdown/aql/primer.md
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@@ -209,7 +209,8 @@
creates a secondary index on a field of one of the datasets.
The first one indexes the FacebookUsers dataset on its user-since field.
This index will be a B+ tree index; its type is unspecified and _btree_ is the default type.
-=======
+The other three illustrate how you can explicitly specify the desired type of index.
+In addition to btree, _rtree_ and inverted _keyword_ indexes are supported by AsterixDB.
Indexes can also have composite keys, and more advanced text indexing is available as well
(ngram(k), where k is the desired gram length).