Merge pull request #25 from rlaiola/piasterisk

Add project all columns (π *) to relational algebra

src/db/parser/grammar_ra.d.ts

@@ -79,6 +79,12 @@ declare module relalgAst {
 		relAlias: string | null,
 	}
 
+	interface columnAsterisk {
+		type: 'column',
+		name: '*',
+		relAlias: string | null
+	}
+
 	interface namedColumnExpr {
 		type: 'namedColumnExpr',
 		name: string,
@@ -139,7 +145,7 @@ declare module relalgAst {
 		child: relalgOperation,
 		child2?: undefined,
 		assignments?: undefined,
-		arg: (namedColumnExpr | columnName)[],
+		arg: (namedColumnExpr | columnName | columnAsterisk)[],
 
 		wrappedInParentheses?: boolean,
 		metaData?: { [key: string]: any },

src/db/parser/grammar_ra.pegjs

@@ -254,6 +254,17 @@ columnName
 			relAlias: relAlias
 		};
 	}
+
+columnAsterisk
+= relAlias:(relationName '.')? '*'
+	{
+		return {
+			type: 'column',
+			name: '*',
+			relAlias: relAlias ? relAlias[0] : null
+		};
+	}
+
 / relAlias:(relationName '.')? '[' index:$[0-9]+ ']'
 	{
 		if(relAlias != null)
@@ -442,6 +453,11 @@ namedColumnExpr
 	{
 		return a;
 	}
+/ col:columnAsterisk
+	{
+		col.alias = null;
+		return col;
+	}
 
 // list of columns (kd.id, kd.name, test) e.g. for the projection
 listOfNamedColumnExpressions

src/db/tests/translate_tests_ra.ts

@@ -254,6 +254,24 @@ QUnit.test('test selection with xor', function (assert) {
 	assert.deepEqual(root.getResult(), ref.getResult());
 });
 
+QUnit.test('test projection[*](R)', function (assert) {
+	const relations = getTestRelations();
+	const query = 'pi * (R)';
+	const root = exec_ra(query, relations);
+
+	const ref = exec_ra(`{
+		R.a, R.b, R.c
+
+		1, 'a', 'd'
+		3, 'c', 'c'
+		4, 'd', 'f'
+		5, 'd', 'b'
+		6, 'e', 'f'
+	}`, relations);
+
+	assert.deepEqual(root.getResult(), ref.getResult());
+});
+
 QUnit.test('test projection[a, b](R)', function (assert) {
 	const relations = getTestRelations();
 	const query = 'pi a, b (R)';
@@ -301,6 +319,22 @@ QUnit.test('test projection[b, a, a, b](R)', function (assert) {
 	}
 });
 
+QUnit.test('test (pi * (R)) inner join [R.b = S.b] (pi * (S))', function (assert) {
+	const relations = getTestRelations();
+	const root = exec_ra('(R) inner join R.b = S.b (S)', relations);
+	const ref = exec_ra(`{
+		R.a:number, R.b:string, R.c:string, S.b:string, S.d:number
+
+		1,          'a',        'd',        'a',        100
+		3,          'c',        'c',        'c',        400
+		4,          'd',        'f',        'd',        200
+		5,          'd',        'b',        'd',        200
+		6,          'e',        'f',        'e',        150
+	}`, relations);
+
+	assert.deepEqual(root.getResult(), ref.getResult());
+});
+
 QUnit.test('test (R) inner join [R.b = S.b] join (S)', function (assert) {
 	const relations = getTestRelations();
 	const root = exec_ra('(R) inner join R.b = S.b (S)', relations);

src/db/translate/relalgFromAst.ts

@@ -526,7 +526,17 @@ export function relalgFromRelalgAstNode(astNode: relalgAst.relalgOperation, rela
 					for (let i = 0; i < n.arg.length; i++) {
 						const el = n.arg[i];
 
-						if (el.type === 'columnName') {
+						if (el.type === 'column' &&
+						    el.name === '*' &&
+								el.relAlias === null) {
+							// project all columns
+							let cols = child.getSchema();
+							for (let i = 0; i < cols.getSize(); i++) {
+								// normal columns
+								projections.push(cols.getColumn(i));
+							}
+						}
+						else if (el.type === 'columnName') {
 							const e = el as relalgAst.columnName;
 							projections.push(new Column(e.name, e.relAlias));
 						}