[parser] parser: support check constraints field (pingcap#871)

parser/ast/ddl.go

@@ -477,6 +477,8 @@ type ColumnOption struct {
 	AutoRandomBitLength int
 	// Enforced is only for Check, default is true.
 	Enforced bool
+	// Name is only used for Check Constraint name.
+	ConstraintName string
 }
 
 // Restore implements Node interface.
@@ -534,6 +536,11 @@ func (n *ColumnOption) Restore(ctx *format.RestoreCtx) error {
 		ctx.WriteKeyWord("COLLATE ")
 		ctx.WritePlain(n.StrValue)
 	case ColumnOptionCheck:
+		if n.ConstraintName != "" {
+			ctx.WriteKeyWord("CONSTRAINT ")
+			ctx.WriteName(n.ConstraintName)
+			ctx.WritePlain(" ")
+		}
 		ctx.WriteKeyWord("CHECK")
 		ctx.WritePlain("(")
 		if err := n.Expr.Restore(ctx); err != nil {
@@ -702,6 +709,10 @@ type Constraint struct {
 	Expr ExprNode // Used for Check
 
 	Enforced bool // Used for Check
+
+	InColumn bool // Used for Check
+
+	InColumnName string // Used for Check
 }
 
 // Restore implements Node interface.

parser/model/model.go

@@ -212,22 +212,24 @@ type TableInfo struct {
 	Charset string `json:"charset"`
 	Collate string `json:"collate"`
 	// Columns are listed in the order in which they appear in the schema.
-	Columns     []*ColumnInfo `json:"cols"`
-	Indices     []*IndexInfo  `json:"index_info"`
-	ForeignKeys []*FKInfo     `json:"fk_info"`
-	State       SchemaState   `json:"state"`
+	Columns     []*ColumnInfo     `json:"cols"`
+	Indices     []*IndexInfo      `json:"index_info"`
+	Constraints []*ConstraintInfo `json:"constraint_info"`
+	ForeignKeys []*FKInfo         `json:"fk_info"`
+	State       SchemaState       `json:"state"`
 	// PKIsHandle is true when primary key is a single integer column.
 	PKIsHandle bool `json:"pk_is_handle"`
 	// IsCommonHandle is true when clustered index feature is
 	// enabled and the primary key is not a single integer column.
 	IsCommonHandle bool `json:"is_common_handle"`
 
-	Comment     string `json:"comment"`
-	AutoIncID   int64  `json:"auto_inc_id"`
-	AutoIdCache int64  `json:"auto_id_cache"`
-	AutoRandID  int64  `json:"auto_rand_id"`
-	MaxColumnID int64  `json:"max_col_id"`
-	MaxIndexID  int64  `json:"max_idx_id"`
+	Comment         string `json:"comment"`
+	AutoIncID       int64  `json:"auto_inc_id"`
+	AutoIdCache     int64  `json:"auto_id_cache"`
+	AutoRandID      int64  `json:"auto_rand_id"`
+	MaxColumnID     int64  `json:"max_col_id"`
+	MaxIndexID      int64  `json:"max_idx_id"`
+	MaxConstraintID int64  `json:"max_cst_id"`
 	// UpdateTS is used to record the timestamp of updating the table's schema information.
 	// These changing schema operations don't include 'truncate table' and 'rename table'.
 	UpdateTS uint64 `json:"update_timestamp"`
@@ -770,6 +772,27 @@ func (index *IndexInfo) HasPrefixIndex() bool {
 	return false
 }
 
+// ConstraintInfo provides meta data describing check-expression constraint.
+type ConstraintInfo struct {
+	ID             int64       `json:"id"`
+	Name           CIStr       `json:"constraint_name"`
+	Table          CIStr       `json:"tbl_name"`        // Table name.
+	ConstraintCols []CIStr     `json:"constraint_cols"` // Depended column names.
+	Enforced       bool        `json:"enforced"`
+	InColumn       bool        `json:"in_column"` // Indicate whether the constraint is column type check.
+	ExprString     string      `json:"expr_string"`
+	State          SchemaState `json:"state"`
+}
+
+// Clone clones ConstraintInfo.
+func (ci *ConstraintInfo) Clone() *ConstraintInfo {
+	nci := *ci
+
+	nci.ConstraintCols = make([]CIStr, len(ci.ConstraintCols))
+	copy(nci.ConstraintCols, ci.ConstraintCols)
+	return &nci
+}
+
 // FKInfo provides meta data describing a foreign key constraint.
 type FKInfo struct {
 	ID       int64       `json:"id"`

parser/parser.y

@@ -2577,6 +2577,10 @@ ColumnOption:
 			Expr:     $4,
 			Enforced: true,
 		}
+		// Keep the column type check constraint name.
+		if $1 != nil {
+			optionCheck.ConstraintName = $1.(string)
+		}
 		switch $6.(int) {
 		case 0:
 			$$ = []*ast.ColumnOption{optionCheck, {Tp: ast.ColumnOptionNotNull}}

parser/parser_test.go

@@ -2822,11 +2822,11 @@ func (s *testParserSuite) TestDDL(c *C) {
 		{"ALTER TABLE ident ADD ( CONSTRAINT FOREIGN KEY ident ( EXECUTE ( 123 ) ) REFERENCES t ( a ) MATCH SIMPLE ON DELETE CASCADE ON UPDATE SET NULL )", true, "ALTER TABLE `ident` ADD COLUMN (CONSTRAINT `ident` FOREIGN KEY (`EXECUTE`(123)) REFERENCES `t`(`a`) MATCH SIMPLE ON DELETE CASCADE ON UPDATE SET NULL)"},
 		// for CONSTRAINT cont'd, the following tests are for another aspect of the incompatibility
 		{"ALTER TABLE t ADD COLUMN a DATE CHECK ( a > 0 ) FIRST", true, "ALTER TABLE `t` ADD COLUMN `a` DATE CHECK(`a`>0) ENFORCED FIRST"},
-		{"ALTER TABLE t ADD a1 int CONSTRAINT ident CHECK ( a1 > 1 ) REFERENCES b ON DELETE CASCADE ON UPDATE CASCADE;", true, "ALTER TABLE `t` ADD COLUMN `a1` INT CHECK(`a1`>1) ENFORCED REFERENCES `b` ON DELETE CASCADE ON UPDATE CASCADE"},
+		{"ALTER TABLE t ADD a1 int CONSTRAINT ident CHECK ( a1 > 1 ) REFERENCES b ON DELETE CASCADE ON UPDATE CASCADE;", true, "ALTER TABLE `t` ADD COLUMN `a1` INT CONSTRAINT `ident` CHECK(`a1`>1) ENFORCED REFERENCES `b` ON DELETE CASCADE ON UPDATE CASCADE"},
 		{"ALTER TABLE t ADD COLUMN a DATE CONSTRAINT CHECK ( a > 0 ) FIRST", true, "ALTER TABLE `t` ADD COLUMN `a` DATE CHECK(`a`>0) ENFORCED FIRST"},
-		{"ALTER TABLE t ADD a TINYBLOB CONSTRAINT ident CHECK ( 1>2 ) REFERENCES b ON DELETE CASCADE ON UPDATE CASCADE", true, "ALTER TABLE `t` ADD COLUMN `a` TINYBLOB CHECK(1>2) ENFORCED REFERENCES `b` ON DELETE CASCADE ON UPDATE CASCADE"},
-		{"ALTER TABLE t ADD a2 int CONSTRAINT ident CHECK (a2 > 1) ENFORCED", true, "ALTER TABLE `t` ADD COLUMN `a2` INT CHECK(`a2`>1) ENFORCED"},
-		{"ALTER TABLE t ADD a2 int CONSTRAINT ident CHECK (a2 > 1) NOT ENFORCED", true, "ALTER TABLE `t` ADD COLUMN `a2` INT CHECK(`a2`>1) NOT ENFORCED"},
+		{"ALTER TABLE t ADD a TINYBLOB CONSTRAINT ident CHECK ( 1>2 ) REFERENCES b ON DELETE CASCADE ON UPDATE CASCADE", true, "ALTER TABLE `t` ADD COLUMN `a` TINYBLOB CONSTRAINT `ident` CHECK(1>2) ENFORCED REFERENCES `b` ON DELETE CASCADE ON UPDATE CASCADE"},
+		{"ALTER TABLE t ADD a2 int CONSTRAINT ident CHECK (a2 > 1) ENFORCED", true, "ALTER TABLE `t` ADD COLUMN `a2` INT CONSTRAINT `ident` CHECK(`a2`>1) ENFORCED"},
+		{"ALTER TABLE t ADD a2 int CONSTRAINT ident CHECK (a2 > 1) NOT ENFORCED", true, "ALTER TABLE `t` ADD COLUMN `a2` INT CONSTRAINT `ident` CHECK(`a2`>1) NOT ENFORCED"},
 		{"ALTER TABLE t ADD a2 int CONSTRAINT ident primary key REFERENCES b ON DELETE CASCADE ON UPDATE CASCADE;", false, ""},
 		{"ALTER TABLE t ADD a2 int CONSTRAINT ident primary key (a2))", false, ""},
 		{"ALTER TABLE t ADD a2 int CONSTRAINT ident unique key (a2))", false, ""},