mysql update docs with env vars, update test with json field, fill cl…

.gitignore

@@ -0,0 +1 @@
+/.idea/

README.md

@@ -480,7 +480,9 @@ go test --tags=exp ./...
 
 To run the tests in the examples folder, a running PostgreSQL instance is
 required. The tests use the following environment variables to connect to the
-database:
+database
+
+#### For PostgreSQL
 
 ```
 Variable     Default Value
@@ -492,6 +494,18 @@ PG_PASSWORD  mysecretpassword
 PG_DATABASE  dinotest
 ```
 
+#### For MySQL
+
+```
+Variable     Default Value
+-------------------------
+MYSQL_HOST      127.0.0.1
+MYSQL_PORT      3306
+MYSQL_USER      root
+MYSQL_ROOT_PASSWORD  mysecretpassword
+MYSQL_DATABASE  dinotest
+```
+
 ```
 go test --tags=examples,exp ./...
 ```

internal/sqltest/mysql.go

@@ -76,5 +76,10 @@ func MySQL(t *testing.T, migrations []string) (*sql.DB, func()) {
 		}
 	}
 
-	return sdb, func() {}
+	return sdb, func() {
+		// Drop the test db after test runs
+		if _, err := db.Exec("DROP DATABASE " + dbName); err != nil {
+			t.Fatal(err)
+		}
+	}
 }