Add support for Teradata trim()

src/test/java/com/alibaba/druid/bvt/sql/teradata/TeradataSelectTest_3.java

@@ -0,0 +1,45 @@
+package com.alibaba.druid.bvt.sql.teradata;
+
+import java.util.List;
+
+import org.junit.Assert;
+
+import com.alibaba.druid.sql.TeradataTest;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
+import com.alibaba.druid.sql.dialect.oracle.parser.OracleStatementParser;
+import com.alibaba.druid.sql.dialect.teradata.parser.TeradataStatementParser;
+import com.alibaba.druid.sql.dialect.teradata.visitor.TeradataSchemaStatVisitor;
+import com.alibaba.druid.stat.TableStat;
+import com.alibaba.druid.stat.TableStat.Column;
+
+public class TeradataSelectTest_3 extends TeradataTest {
+	public void test_trim() throws Exception {
+        String sql = "select trim(trailing from columnname) from dbc.columnsv;";
+		
+        TeradataStatementParser parser = new TeradataStatementParser(sql);
+        List<SQLStatement> statementList = parser.parseStatementList();
+        SQLStatement stmt = statementList.get(0);
+        
+        Assert.assertTrue(stmt instanceof SQLSelectStatement);
+        print(statementList);
+        
+        TeradataSchemaStatVisitor visitor = new TeradataSchemaStatVisitor();
+        stmt.accept(visitor);
+
+        System.out.println("Tables : " + visitor.getTables());
+        System.out.println("fields : " + visitor.getColumns());
+        System.out.println("coditions : " + visitor.getConditions());
+        System.out.println("orderBy : " + visitor.getOrderByColumns());
+
+        Assert.assertEquals(1, visitor.getTables().size());
+        Assert.assertEquals(1, visitor.getColumns().size());
+        Assert.assertEquals(0, visitor.getConditions().size());
+
+        Assert.assertTrue(visitor.getTables().containsKey(new TableStat.Name("dbc.columnsv")));
+
+        Assert.assertTrue(visitor.getColumns().contains(new Column("dbc.columnsv", "columnname")));
+        System.out.println("------ end of " + new Object(){}.getClass().getEnclosingMethod().getName() + " ------");
+	
+	}
+}