add testcase

src/test/java/com/alibaba/druid/bvt/sql/postgresql/ddl/PGAlterTableAlterColumnTest0.java

@@ -0,0 +1,38 @@
+package com.alibaba.druid.bvt.sql.postgresql.ddl;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.postgresql.parser.PGSQLStatementParser;
+import com.alibaba.druid.sql.dialect.postgresql.visitor.PGSchemaStatVisitor;
+import com.alibaba.druid.stat.TableStat;
+import org.junit.Assert;
+
+import java.util.List;
+
+
+public class PGAlterTableAlterColumnTest0 extends PGTest {
+    public void test_0 () throws Exception {
+        String sql = "ALTER TABLE organizations ALTER COLUMN guarded TYPE BOOLEAN, ALTER COLUMN guarded DROP NOT NULL";
+
+        PGSQLStatementParser parser = new PGSQLStatementParser(sql);
+        List<SQLStatement> statementList = parser.parseStatementList();
+        SQLStatement stmt = statementList.get(0);
+        assertEquals("ALTER TABLE organizations\n" +
+                "\tALTER COLUMN guarded BOOLEAN,\n" +
+                "\tALTER COLUMN guarded DROP NOT NULL", stmt.toString());
+
+        Assert.assertEquals(1, statementList.size());
+
+        PGSchemaStatVisitor visitor = new PGSchemaStatVisitor();
+        stmt.accept(visitor);
+
+        System.out.println("Tables : " + visitor.getTables());
+        System.out.println("fields : " + visitor.getColumns());
+
+        Assert.assertTrue(visitor.getTables().containsKey(new TableStat.Name("organizations")));
+        
+        Assert.assertTrue(visitor.getTables().get(new TableStat.Name("organizations")).getAlterCount() == 1);
+
+        Assert.assertTrue(visitor.getColumns().size() == 1);
+    }
+}