entc/gen: merge list of entsql annotation to one (#928)

dialect/entsql/annotation.go

@@ -16,7 +16,24 @@ type Annotation struct {
 	//		Table: "Users",
 	//	}
 	//
-	Table string
+	Table string `json:"table,omitempty"`
+
+	// Charset defines the character-set of the table. For example:
+	//
+	//	entsql.Annotation{
+	//		Charset: "utf8mb4",
+	//	}
+	//
+	Charset string `json:"charset,omitempty"`
+
+	// Collation defines the collation of the table (a set of rules for comparing
+	// characters in a character set). For example:
+	//
+	//	entsql.Annotation{
+	//		Collation: "utf8mb4_bin",
+	//	}
+	//
+	Collation string `json:"collation,omitempty"`
 }
 
 // Name describes the annotation name.

dialect/sql/schema/schema.go

@@ -10,6 +10,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/facebook/ent/dialect/entsql"
 	"github.com/facebook/ent/dialect/sql"
 	"github.com/facebook/ent/schema/field"
 )
@@ -33,6 +34,7 @@ type Table struct {
 	Indexes     []*Index
 	PrimaryKey  []*Column
 	ForeignKeys []*ForeignKey
+	Annotation  *entsql.Annotation
 }
 
 // NewTable returns a new table with the given name.
@@ -63,6 +65,12 @@ func (t *Table) AddColumn(c *Column) *Table {
 	return t
 }
 
+// SetAnnotation the entsql.Annotation on the table.
+func (t *Table) SetAnnotation(ant *entsql.Annotation) *Table {
+	t.Annotation = ant
+	return t
+}
+
 // AddIndex creates and adds a new index to the table from the given options.
 func (t *Table) AddIndex(name string, unique bool, columns []string) *Table {
 	return t.addIndex(&Index{