add tests for scylladb. add scylladb to docs

Author: mkorolyov

README.md

@@ -29,6 +29,7 @@ Database drivers run migrations. [Add a new database?](database/driver.go)
 * [Redshift](database/redshift)
 * [Ql](database/ql)
 * [Cassandra](database/cassandra)
+* [ScyllaDB](database/cassandra)
 * [SQLite](database/sqlite)
 * [SQLite3](database/sqlite3) ([todo #165](https://github.com/mattes/migrate/issues/165))
 * [SQLCipher](database/sqlcipher)

database/cassandra/README.md

@@ -1,11 +1,12 @@
-# Cassandra
+# Cassandra / ScyllaDB
 
 * Drop command will not work on Cassandra 2.X because it rely on
-system_schema table which comes with 3.X
+system_schema table which comes with 3.X. Works as expected for ScyllaDB.
 * Other commands should work properly but are **not tested**
 * The Cassandra driver (gocql) does not natively support executing multiple statements in a single query. To allow for multiple statements in a single migration, you can use the `x-multi-statement` param. There are two important caveats:
   * This mode splits the migration text into separately-executed statements by a semi-colon `;`. Thus `x-multi-statement` cannot be used when a statement in the migration contains a string with a semi-colon.
   * The queries are not executed in any sort of transaction/batch, meaning you are responsible for fixing partial migrations.
+* For ScyllaDB no additional configuration required as it is a drop-in replacement for Cassandra.
 
 
 ## Usage

database/cassandra/cassandra_test.go

@@ -25,9 +25,11 @@ var (
 	// Although Cassandra 2.x is supported by the Apache Foundation,
 	// the migrate db driver only supports Cassandra 3.x since it uses
 	// the system_schema keyspace.
+	// last ScyllaDB version tested is 5.1.11
 	specs = []dktesting.ContainerSpec{
 		{ImageName: "cassandra:3.0", Options: opts},
 		{ImageName: "cassandra:3.11", Options: opts},
+		{ImageName: "scylladb/scylla:5.1.11", Options: opts},
 	}
 )