fix: Pass file_format values as-is in external table configuration

Common use of FILE_FORMAT under CREATE EXTERNAL TABLE includes specifying
a previously created format name (FORMAT_NAME = 'NAME') or the various
type options (TYPE=CSV FIELD_DELIMITER='|').

Both of these usage require defining string literals with the single quote
character (') that should not be escaped.

This change removes the escaping of single quotes performed for the
file_format values.

Some examples have also been added to the field documentation
to make it easier to understand how values need to be passed to
external tables.

Testing:

  - Modified unit tests to exercise passing of typical file format values
  - Ran 'make test' to confirm existing tests continue to pass
  - Attempted an external table creation on a personal account with the
    changes included and observed it to execute a successful SQL

Fixes Snowflake-Labs#1046

examples/resources/snowflake_external_table/resource.tf

@@ -1,8 +1,9 @@
 resource snowflake_external_table external_table {
-  database = "db"
-  schema   = "schema"
-  name     = "external_table"
-  comment  = "External table"
+  database    = "db"
+  schema      = "schema"
+  name        = "external_table"
+  comment     = "External table"
+  file_format = "TYPE = CSV FIELD_DELIMITER = '|'"
 
   column {
     name = "id"

pkg/resources/external_table.go

@@ -74,7 +74,7 @@ var externalTableSchema = map[string]*schema.Schema{
 		Type:        schema.TypeString,
 		Required:    true,
 		ForceNew:    true,
-		Description: "Specifies the file format for the external table.",
+		Description: "Specifies the file format options for the external table.",
 	},
 	"pattern": {
 		Type:        schema.TypeString,

pkg/resources/external_table_test.go

@@ -27,13 +27,13 @@ func TestExternalTableCreate(t *testing.T) {
 		"comment":     "great comment",
 		"column":      []interface{}{map[string]interface{}{"name": "column1", "type": "OBJECT", "as": "a"}, map[string]interface{}{"name": "column2", "type": "VARCHAR", "as": "b"}},
 		"location":    "location",
-		"file_format": "format",
+		"file_format": "FORMAT_NAME = 'format'",
 		"pattern":     "pattern",
 	}
 	d := externalTable(t, "database_name|schema_name|good_name", in)
 
 	WithMockDb(t, func(db *sql.DB, mock sqlmock.Sqlmock) {
-		mock.ExpectExec(`CREATE EXTERNAL TABLE "database_name"."schema_name"."good_name" \("column1" OBJECT AS a, "column2" VARCHAR AS b\) WITH LOCATION = location REFRESH_ON_CREATE = true AUTO_REFRESH = true PATTERN = 'pattern' FILE_FORMAT = \( format \) COMMENT = 'great comment'`).WillReturnResult(sqlmock.NewResult(1, 1))
+		mock.ExpectExec(`CREATE EXTERNAL TABLE "database_name"."schema_name"."good_name" \("column1" OBJECT AS a, "column2" VARCHAR AS b\) WITH LOCATION = location REFRESH_ON_CREATE = true AUTO_REFRESH = true PATTERN = 'pattern' FILE_FORMAT = \( FORMAT_NAME = 'format' \) COMMENT = 'great comment'`).WillReturnResult(sqlmock.NewResult(1, 1))
 
 		expectExternalTableRead(mock)
 		err := resources.CreateExternalTable(d, db)

pkg/snowflake/external_table.go

@@ -141,7 +141,7 @@ func (tb *ExternalTableBuilder) Create() string {
 		q.WriteString(fmt.Sprintf(` PATTERN = '%v'`, EscapeString(tb.pattern)))
 	}
 
-	q.WriteString(fmt.Sprintf(` FILE_FORMAT = ( %v )`, EscapeString(tb.fileFormat)))
+	q.WriteString(fmt.Sprintf(` FILE_FORMAT = ( %v )`, tb.fileFormat))
 
 	if tb.awsSNSTopic != "" {
 		q.WriteString(fmt.Sprintf(` AWS_SNS_TOPIC = '%v'`, EscapeString(tb.awsSNSTopic)))

pkg/snowflake/external_table_test.go

@@ -12,13 +12,13 @@ func TestExternalTableCreate(t *testing.T) {
 	s.WithColumns([]map[string]string{{"name": "column1", "type": "OBJECT", "as": "expression1"}, {"name": "column2", "type": "VARCHAR", "as": "expression2"}})
 	s.WithLocation("location")
 	s.WithPattern("pattern")
-	s.WithFileFormat("file format")
+	s.WithFileFormat("TYPE = CSV FIELD_DELIMITER = '|'")
 	r.Equal(s.QualifiedName(), `"test_db"."test_schema"."test_table"`)
 
-	r.Equal(s.Create(), `CREATE EXTERNAL TABLE "test_db"."test_schema"."test_table" ("column1" OBJECT AS expression1, "column2" VARCHAR AS expression2) WITH LOCATION = location REFRESH_ON_CREATE = false AUTO_REFRESH = false PATTERN = 'pattern' FILE_FORMAT = ( file format )`)
+	r.Equal(s.Create(), `CREATE EXTERNAL TABLE "test_db"."test_schema"."test_table" ("column1" OBJECT AS expression1, "column2" VARCHAR AS expression2) WITH LOCATION = location REFRESH_ON_CREATE = false AUTO_REFRESH = false PATTERN = 'pattern' FILE_FORMAT = ( TYPE = CSV FIELD_DELIMITER = '|' )`)
 
 	s.WithComment("Test Comment")
-	r.Equal(s.Create(), `CREATE EXTERNAL TABLE "test_db"."test_schema"."test_table" ("column1" OBJECT AS expression1, "column2" VARCHAR AS expression2) WITH LOCATION = location REFRESH_ON_CREATE = false AUTO_REFRESH = false PATTERN = 'pattern' FILE_FORMAT = ( file format ) COMMENT = 'Test Comment'`)
+	r.Equal(s.Create(), `CREATE EXTERNAL TABLE "test_db"."test_schema"."test_table" ("column1" OBJECT AS expression1, "column2" VARCHAR AS expression2) WITH LOCATION = location REFRESH_ON_CREATE = false AUTO_REFRESH = false PATTERN = 'pattern' FILE_FORMAT = ( TYPE = CSV FIELD_DELIMITER = '|' ) COMMENT = 'Test Comment'`)
 }
 
 func TestExternalTableUpdate(t *testing.T) {