Update docs to include new FDW features + elasticsearch FDW

Author: mildbyte

content/docs/0000_getting-started/0100_introduction.mdx

@@ -25,7 +25,7 @@ You do not need to download the full Splitgraph image to query it. Instead, you
 
 Splitgraph does not limit your data sources to Postgres databases. It includes first-class support for importing and querying data from other databases using Postgres [foreign data wrappers](../ingesting-data/foreign-data-wrappers/introduction). You can create Splitgraph images or query data in [MongoDB](../ingesting-data/foreign-data-wrappers/load-mongo-collections),
 [MySQL](../ingesting-data/foreign-data-wrappers/load-mysql-tables),
-[CSV files](../ingesting-data/load-csv-files) or [other Postgres databases](../ingesting-data/foreign-data-wrappers/load-postgres-tables) using the same interface.
+[CSV files](../ingesting-data/load-csv-files), [other Postgres databases](../ingesting-data/foreign-data-wrappers/load-postgres-tables) or even [Elasticsearch clusters](../ingesting-data/foreign-data-wrappers/load-elasticsearch-index) using the same interface.
 
 Finally, Splitgraph is peer-to-peer. You can push and pull data images between other Splitgraph installations and use it as a standalone tool to supercharge your data workflows.
 

content/docs/0000_getting-started/0150_frequently-asked-questions.mdx

@@ -71,7 +71,7 @@ which will let you ingest data from existing databases without installing Splitg
 
 ### Does my data have to be in PostgreSQL to use Splitgraph?
 
-With [mounting](../concepts/mounting), you can query data in other databases (including MongoDB, MySQL or PostgreSQL) directly through Spligraph with
+With [mounting](../concepts/mounting), you can query data in other databases (including MongoDB, MySQL, PostgreSQL or Elasticsearch) directly through Spligraph with
 [any PostgreSQL client](../integrating-splitgraph/other-clients). You do not need to copy your data into PostgreSQL to use Splitgraph.
 
 ### Why PostgreSQL? Why not write your own database?

content/docs/0300_ingesting-data/0300_foreign-data-wrappers/0100_introduction.mdx

@@ -9,4 +9,4 @@ Foreign tables act similarly to normal tables and can accept the same SQL querie
 
 In Splitgraph terminology, this is called "mounting", kind of like mounting a filesystem to mount points in the directory tree. You can snapshot these mounted tables, turning them into Splitgraph images, with the [`sgr import`](../../sgr/image-management-creation/import) command.
 
-The Splitgraph engine ships with several open-source foreign data wrappers: [`postgres_fdw`](https://www.postgresql.org/docs/12/postgres-fdw.html), [`mongo_fdw`](https://github.com/EnterpriseDB/mongo_fdw) and [`mysql_fdw`](https://github.com/EnterpriseDB/mysql_fdw).
+The Splitgraph engine ships with several open-source foreign data wrappers: [`postgres_fdw`](https://www.postgresql.org/docs/12/postgres-fdw.html), [`mongo_fdw`](https://github.com/EnterpriseDB/mongo_fdw), [`mysql_fdw`](https://github.com/EnterpriseDB/mysql_fdw) and  [`pg_es_fdw`](https://github.com/splitgraph/postgres-elasticsearch-fdw).

content/docs/0300_ingesting-data/0300_foreign-data-wrappers/0300_load-postgres-tables.mdx

@@ -6,13 +6,29 @@ export const meta = {
 To use [`postgres_fdw`](https://www.postgresql.org/docs/12/postgres-fdw.html) and mount remote PostgreSQL databases, run:
 
 ```
-$ sgr mount postgres_fdw \\
-    -c username:password@server:port \\
-    -o '{"dbname": remote_db_name, "remote_schema": remote_schema_name, \\
-        "tables_to_mount": ["table_1", "table_2"]}' \\
-    local_schema
+$ sgr mount postgres_fdw local_schema -c username:password@server:port -o@- <<EOF
+{
+    "dbname": remote_db_name,
+    "remote_schema": remote_schema_name,
+    "tables": ["table_1", "table_2"],
+    "extra_server_args": [optional, e.g. {"use_remote_estimate": "true"}]
+}
+EOF
 ```
 
-`"tables_to_mount"` can be omitted (in which case all tables in `remote_schema` will be mounted into `local_schema`).
+`"tables"` can be omitted (in which case all tables in `remote_schema` will be mounted into `local_schema`).
+
+You can also pass a dictionary of tables and their schema as `tables`. This will override the schema that's inferred by `IMPORT FOREIGN SCHEMA`. For example:
+
+```json
+{
+    "tables": {
+        "table_1": {
+            "col_1": "integer",
+            "col_2": "text"
+        }
+    }
+}
+```
 
 To snapshot the data, making it part of an actual Splitgraph image, use the [`sgr import`](../../sgr/image-management-creation/import) command.

content/docs/0300_ingesting-data/0300_foreign-data-wrappers/0400_load-mysql-tables.mdx

@@ -6,12 +6,31 @@ export const meta = {
 To mount a MySQL database into the Splitgraph engine using [`mysql_fdw`](https://github.com/EnterpriseDB/mysql_fdw), run:
 
 ```
-$ sgr mount mysql_fdw -c username:password@host:port \\
-    -o '{"remote_schema": "remote_schema"}' schema_name
+$ sgr mount mysql_fdw local_schema -c username:password@host:port -o@- <<EOF
+{
+    "remote_schema": "remote_schema",
+    "tables": ["table_1"],
+}
+
 ```
 
 This will mount a MySQL schema `remote_schema` into a local schema `schema_name` on the
 Splitgraph engine. Note that if your MySQL server is running on localhost and you wish to
 access it over a TCP connection, you should use `127.0.0.1` instead of `localhost` as the `host`.
 
+`"tables"` can be omitted (in which case all tables in `remote_schema` will be mounted into `local_schema`).
+
+You can also pass a dictionary of tables and their schema as `tables`. This will override the schema that's inferred by `IMPORT FOREIGN SCHEMA`. For example:
+
+```json
+{
+    "tables": {
+        "table_1": {
+            "col_1": "integer",
+            "col_2": "text"
+        }
+    }
+}
+```
+
 To snapshot the table, making it part of an actual Splitgraph image, use the [`sgr import`](../../sgr/image-management-creation/import) command.

content/docs/0300_ingesting-data/0300_foreign-data-wrappers/0450_load-elasticsearch-index.mdx

@@ -0,0 +1,31 @@
+export const meta = {
+  id: "load-elasticsearch-index",
+  title: "Loading Elasticsearch indexes",
+};
+
+To mount a remote Elasticsearch index into the Splitgraph engine using Splitgraph's fork of [`pg_es_fdw`](https://github.com/splitgraph/postgres-elasticsearch-fdw), run:
+
+```
+$ sgr mount elasticsearch -c elasticsearch:9200 -o@- <<EOF
+    {
+      "table_spec": {
+        "table_1": {
+          "schema": {
+            "id": "text",
+            "@timestamp": "timestamp",
+            "query": "text",
+            "col_1": "text",
+            "col_2": "boolean",
+          },
+          "index": "index-pattern*",
+          "rowid_column": "id",
+          "query_column": "query",
+        }
+      }
+    }
+EOF
+```
+
+The FDW translates local queries into the [Elasticsearch Query DSL](https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl.html). You can also pass Lucene query strings as `query_column` equality clauses. For example, if `query_column` is set to `query`, you can use `WHERE query='text_body:chess'`).
+
+To snapshot the table, making it part of an actual Splitgraph image, use the [`sgr import`](../../sgr/image-management-creation/import) command.