Log a SQL warning when historical values don't fit in dolt_diff_<tablename>'s schema

go/libraries/doltcore/rowconv/row_converter.go

@@ -32,10 +32,12 @@ var IdentityConverter = &RowConverter{nil, true, nil}
 // to take an extra action when a value cannot be automatically converted to the output data type.
 type WarnFunction func(int, string, ...interface{})
 
-var DatatypeCoercionFailureWarning = "unable to coerce value from field '%s' into latest column schema"
-
+const DatatypeCoercionFailureWarning = "unable to coerce value from field '%s' into latest column schema"
 const DatatypeCoercionFailureWarningCode int = 1105 // Since this our own custom warning we'll use 1105, the code for an unknown error
 
+const TruncatedOutOfRangeValueWarning = "Truncated incorrect %v value: %v"
+const TruncatedOutOfRangeValueWarningCode = 1292
+
 // RowConverter converts rows from one schema to another
 type RowConverter struct {
 	// FieldMapping is a mapping from source column to destination column

go/libraries/doltcore/sqle/dtables/diff_table.go

@@ -98,13 +98,6 @@ func NewDiffTable(ctx *sql.Context, tblName string, ddb *doltdb.DoltDB, root *do
 		return nil, err
 	}
 
-	// Process sch to widen all the fields so that any previous values (in the same type family) can be
-	// shown in the diff table, even if the current schema's type has been changed to a smaller type.
-	sch, err = widenSchemaColumns(sch)
-	if err != nil {
-		return nil, err
-	}
-
 	diffTableSchema, j, err := GetDiffTableSchemaAndJoiner(ddb.Format(), sch, sch)
 	if err != nil {
 		return nil, err
@@ -405,21 +398,6 @@ func (dt *DiffTable) reverseIterForChild(ctx *sql.Context, parent hash.Hash) (*d
 	}
 }
 
-// widenSchemaColumns takes a schema, |sch|, and returns a new schema with all the non-PK columns
-// promoted to their widest type in the same family (e.g. tinyint -> bigint, varchar(10) -> TEXT).
-// This function is used so that when a table's schema has changed throughout its history, we can
-// still show any previous values in the diff table, even if those previous values are larger than
-// the current schema's type.
-func widenSchemaColumns(sch schema.Schema) (schema.Schema, error) {
-	widenedCols := make([]schema.Column, 0, sch.GetAllCols().Size())
-	for _, col := range sch.GetAllCols().GetColumns() {
-		col.TypeInfo = col.TypeInfo.Promote()
-		widenedCols = append(widenedCols, col)
-	}
-	return schema.NewSchema(schema.NewColCollection(widenedCols...),
-		[]int{}, sch.GetCollation(), sch.Indexes(), sch.Checks())
-}
-
 func tableInfoForCommit(ctx context.Context, table string, cm *doltdb.Commit, hs hash.Hash) (TblInfoAtCommit, error) {
 	r, err := cm.GetRootValue(ctx)
 	if err != nil {

go/libraries/doltcore/sqle/dtables/prolly_row_conv.go

@@ -109,12 +109,7 @@ func (c ProllyRowConverter) PutConverted(ctx context.Context, key, value val.Tup
 		return err
 	}
 
-	err = c.putFields(ctx, value, c.valProj, c.valDesc, c.nonPkTargetTypes, dstRow)
-	if err != nil {
-		return err
-	}
-
-	return nil
+	return c.putFields(ctx, value, c.valProj, c.valDesc, c.nonPkTargetTypes, dstRow)
 }
 
 func (c ProllyRowConverter) putFields(ctx context.Context, tup val.Tuple, proj val.OrdinalMapping, desc val.TupleDesc, targetTypes []sql.Type, dstRow []interface{}) error {
@@ -135,7 +130,8 @@ func (c ProllyRowConverter) putFields(ctx context.Context, tup val.Tuple, proj v
 				dstRow[j] = nil
 				err = nil
 			} else if !inRange {
-				return sql.ErrValueOutOfRange.New(f, t)
+				c.warnFn(rowconv.TruncatedOutOfRangeValueWarningCode, rowconv.TruncatedOutOfRangeValueWarning, t, f)
+				dstRow[j] = nil
 			} else if err != nil {
 				return err
 			}

go/libraries/doltcore/sqle/enginetest/dolt_queries_diff.go

@@ -419,8 +419,18 @@ var DiffSystemTableScriptTests = []queries.ScriptTest{
 			{
 				Query: "select to_pk, to_col1, to_col2, to_commit, from_pk, from_col1, from_col2, from_commit, diff_type from dolt_diff_t order by diff_type ASC;",
 				Expected: []sql.Row{
-					{1, "123456789012345", 420, doltCommit, nil, nil, nil, doltCommit, "added"},
-					{1, "1234567890", 13, doltCommit, 1, "123456789012345", 420, doltCommit, "modified"},
+					{1, nil, nil, doltCommit, nil, nil, nil, doltCommit, "added"},
+					{1, "1234567890", 13, doltCommit, 1, nil, nil, doltCommit, "modified"},
+				},
+				ExpectedWarningsCount: 4,
+			},
+			{
+				Query: "SHOW WARNINGS;",
+				Expected: []sql.Row{
+					{"Warning", 1292, "Truncated incorrect tinyint value: 420"},
+					{"Warning", 1292, "Truncated incorrect tinyint value: 420"},
+					{"Warning", 1292, "Truncated incorrect varchar(10) value: 123456789012345"},
+					{"Warning", 1292, "Truncated incorrect varchar(10) value: 123456789012345"},
 				},
 			},
 		},