exists

src/defaultHandler.ts

@@ -751,6 +751,22 @@ export class Handler {
             }
             return builder;
         },
+        exists: (handler: Handler, a: allModifierInput[]):QueryBuilder =>{
+            let e = a[0];
+            if (e instanceof Attribute || e instanceof AttributeAlias) return new QueryBuilder([{ data: "exists (" + e.getString(handler) + ")" }])
+            if (e instanceof Modifier || e instanceof selectQuery || e instanceof Aggregation) {
+                const builder = new QueryBuilder();
+                builder.addCode("exists (");
+                builder.append(e.serialize(handler));
+                builder.addCode(")");
+                return builder;
+            }
+            return new QueryBuilder([
+                { data: "exists (" },
+                { inject: true, data: e },
+                { data: ")" }
+            ]);
+        },
         concat: (handler: Handler, a: allModifierInput[]): QueryBuilder => {
             const builder = new QueryBuilder();
             builder.addCode("CONCAT(");

src/funcs.ts

@@ -20,6 +20,8 @@ export const not = (arg: allModifierInput) => new BooleanModifier("not", [arg]);
 export const like = (a: allModifierInput, b: allModifierInput) => new BooleanModifier("like", [a, b]);
 export const regexp = (a: allModifierInput, b: allModifierInput) => new BooleanModifier("regexp", [a, b]);
 
+export const exists = (q: selectQuery) => new BooleanModifier("exists", [q]);
+
 export const concat = (...args: allModifierInput[]) => new StringModifier("concat", args);
 
 //aggregations