ddl: expose getPrimaryKey() as a public method of model.TableInfo (#3…

…5512)

close #35511

ddl/ddl_api.go

@@ -1628,61 +1628,13 @@ func checkInvisibleIndexOnPK(tblInfo *model.TableInfo) error {
 	if tblInfo.PKIsHandle {
 		return nil
 	}
-	pk := getPrimaryKey(tblInfo)
+	pk := tblInfo.GetPrimaryKey()
 	if pk != nil && pk.Invisible {
 		return dbterror.ErrPKIndexCantBeInvisible
 	}
 	return nil
 }
 
-// getPrimaryKey extract the primary key in a table and return `IndexInfo`
-// The returned primary key could be explicit or implicit.
-// If there is no explicit primary key in table,
-// the first UNIQUE INDEX on NOT NULL columns will be the implicit primary key.
-// For more information about implicit primary key, see
-// https://dev.mysql.com/doc/refman/8.0/en/invisible-indexes.html
-func getPrimaryKey(tblInfo *model.TableInfo) *model.IndexInfo {
-	var implicitPK *model.IndexInfo
-
-	for _, key := range tblInfo.Indices {
-		if key.Primary {
-			// table has explicit primary key
-			return key
-		}
-		// The case index without any columns should never happen, but still do a check here
-		if len(key.Columns) == 0 {
-			continue
-		}
-		// find the first unique key with NOT NULL columns
-		if implicitPK == nil && key.Unique {
-			// ensure all columns in unique key have NOT NULL flag
-			allColNotNull := true
-			skip := false
-			for _, idxCol := range key.Columns {
-				col := model.FindColumnInfo(tblInfo.Cols(), idxCol.Name.L)
-				// This index has a column in DeleteOnly state,
-				// or it is expression index (it defined on a hidden column),
-				// it can not be implicit PK, go to next index iterator
-				if col == nil || col.Hidden {
-					skip = true
-					break
-				}
-				if !mysql.HasNotNullFlag(col.GetFlag()) {
-					allColNotNull = false
-					break
-				}
-			}
-			if skip {
-				continue
-			}
-			if allColNotNull {
-				implicitPK = key
-			}
-		}
-	}
-	return implicitPK
-}
-
 func setTableAutoRandomBits(ctx sessionctx.Context, tbInfo *model.TableInfo, colDefs []*ast.ColumnDef) error {
 	pkColName := tbInfo.GetPkName()
 	for _, col := range colDefs {

parser/model/model.go

@@ -808,6 +808,54 @@ func NewExtraPhysTblIDColInfo() *ColumnInfo {
 	return colInfo
 }
 
+// GetPrimaryKey extract the primary key in a table and return `IndexInfo`
+// The returned primary key could be explicit or implicit.
+// If there is no explicit primary key in table,
+// the first UNIQUE INDEX on NOT NULL columns will be the implicit primary key.
+// For more information about implicit primary key, see
+// https://dev.mysql.com/doc/refman/8.0/en/invisible-indexes.html
+func (t *TableInfo) GetPrimaryKey() *IndexInfo {
+	var implicitPK *IndexInfo
+
+	for _, key := range t.Indices {
+		if key.Primary {
+			// table has explicit primary key
+			return key
+		}
+		// The case index without any columns should never happen, but still do a check here
+		if len(key.Columns) == 0 {
+			continue
+		}
+		// find the first unique key with NOT NULL columns
+		if implicitPK == nil && key.Unique {
+			// ensure all columns in unique key have NOT NULL flag
+			allColNotNull := true
+			skip := false
+			for _, idxCol := range key.Columns {
+				col := FindColumnInfo(t.Cols(), idxCol.Name.L)
+				// This index has a column in DeleteOnly state,
+				// or it is expression index (it defined on a hidden column),
+				// it can not be implicit PK, go to next index iterator
+				if col == nil || col.Hidden {
+					skip = true
+					break
+				}
+				if !mysql.HasNotNullFlag(col.GetFlag()) {
+					allColNotNull = false
+					break
+				}
+			}
+			if skip {
+				continue
+			}
+			if allColNotNull {
+				implicitPK = key
+			}
+		}
+	}
+	return implicitPK
+}
+
 // ColumnIsInIndex checks whether c is included in any indices of t.
 func (t *TableInfo) ColumnIsInIndex(c *ColumnInfo) bool {
 	for _, index := range t.Indices {