Copy enumerators from table to view

h2/src/docsrc/html/changelog.html

@@ -21,6 +21,8 @@ Change Log
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #1012: NPE when querying INFORMATION_SCHEMA.COLUMNS on a view that references an ENUM column
+</li>
 <li>Issue #1010: MERGE USING table not found with qualified table
 </li>
 <li>PR #1009: Fix ARRAY_AGG with ORDER BY and refactor aggregates

h2/src/main/org/h2/table/TableView.java

@@ -193,7 +193,13 @@ public class TableView extends Table {
                 long precision = expr.getPrecision();
                 int scale = expr.getScale();
                 int displaySize = expr.getDisplaySize();
-                Column col = new Column(name, type, precision, scale, displaySize);
+                String[] enumerators = null;
+                if (type == Value.ENUM) {
+                    if (expr instanceof ExpressionColumn) {
+                        enumerators = ((ExpressionColumn) expr).getColumn().getEnumerators();
+                    }
+                }
+                Column col = new Column(name, type, precision, scale, displaySize, enumerators);
                 col.setTable(this, i);
                 // Fetch check constraint from view column source
                 ExpressionColumn fromColumn = null;

h2/src/test/org/h2/test/scripts/datatypes/enum.sql

@@ -185,3 +185,22 @@ SELECT * FROM TEST;
 
 DROP TABLE TEST;
 > ok
+
+CREATE TABLE TEST(E ENUM('A', 'B'));
+> ok
+
+CREATE VIEW V AS SELECT * FROM TEST;
+> ok
+
+SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE COLUMN_NAME = 'E' ORDER BY TABLE_NAME;
+> TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_PRECISION_RADIX NUMERIC_SCALE CHARACTER_SET_NAME COLLATION_NAME TYPE_NAME NULLABLE IS_COMPUTED SELECTIVITY CHECK_CONSTRAINT SEQUENCE_NAME REMARKS SOURCE_DATA_TYPE COLUMN_TYPE   COLUMN_ON_UPDATE
+> ------------- ------------ ---------- ----------- ---------------- -------------- ----------- --------- ------------------------ ---------------------- ----------------- ----------------------- ------------- ------------------ -------------- --------- -------- ----------- ----------- ---------------- ------------- ------- ---------------- ------------- ----------------
+> SCRIPT        PUBLIC       TEST       E           1                null           YES         1111      2147483647               2147483647             2147483647        10                      0             Unicode            OFF            ENUM      1        FALSE       50                           null                  null             ENUM('A','B') null
+> SCRIPT        PUBLIC       V          E           1                null           YES         1111      2147483647               2147483647             2147483647        10                      0             Unicode            OFF            ENUM      1        FALSE       50                           null                  null             ENUM('A','B') null
+> rows (ordered): 2
+
+DROP VIEW V;
+> ok
+
+DROP TABLE TEST;
+> ok