generell Aliases

readme.md

@@ -13,6 +13,7 @@ Features:
 - [x] remove unused Schema
 - [x] joins
 - [x] table alias
+- [x] generell aliases
 - [x] unified response
 - [ ] change Schema
 - [ ] Key-Value Store Shortcut
@@ -131,6 +132,7 @@ _Aliases_:
 ```javascript 
 const alias1 = TableA.createAlias("alias1");
 //alias1 can be used like a Table in select Statements.
+const alias2 = alias(avg(TableA.A1), "someAvg");
 ```
 
 Get requestet Data:

src/alias.ts

@@ -1,5 +1,8 @@
 import { Attribute, DB, Table } from "./db.js"
+import { Aggregation, Modifier } from "./dbStructure.js";
 import { Handler } from "./defaultHandler.js";
+import { QueryBuilder, selectQuery } from "./query.js";
+import { selectElements } from "./types.js";
 
 export class AttributeAlias {
     name: string;
@@ -21,8 +24,8 @@ export class AttributeAlias {
     getStringFunc(handler: Handler) {
         return this.table.serialize(handler) + "(" + this.serialize(handler) + ")";
     }
-    toString(){
+    toString() {
-        return this.table.dbLangTableName + "_" + this.name; 
+        return this.table.dbLangTableName + "_" + this.name;
     }
 }
 
@@ -54,4 +57,34 @@ export class TableAlias {
     toString(handler: Handler = this.dbLangDatabaseInstance.getHandler()) {
         return handler.builders.escapeID(this.dbLangTableName);
     }
+}
+
+export class Alias {
+    alias: string;
+    a: selectElements;
+
+    constructor(a: selectElements, alias: string) {
+        this.alias = alias;
+        this.a = a;
+    }
+
+    serialize(handler: Handler) {
+        let builder = new QueryBuilder();
+        if (this.a instanceof Attribute || this.a instanceof AttributeAlias)
+            builder.addCode(this.a.getString(handler) + " " + handler.builders.escapeID(this.a.toString()));
+        else if (this.a instanceof Modifier || this.a instanceof selectQuery || this.a instanceof Aggregation || this.a instanceof Alias) {
+            builder.addCode("(");
+            builder.append(this.a.serialize(handler));
+            builder.addCode(")");
+        } else {
+            builder.addInjection(this.a);
+        }
+        return builder;
+    }
+    getString(handler: Handler) {
+        return this.serialize(handler);
+    }
+    toString() {
+        return this.alias;
+    }
 }

src/defaultHandler.ts

@@ -1,4 +1,4 @@
-import { AttributeAlias, TableAlias } from "./alias.js";
+import { Alias, AttributeAlias, TableAlias } from "./alias.js";
 import { Attribute, DB, insertResponse, readResponse, Table, writeResponse } from "./db.js"
 import { Aggregation, checkConstraint, joinCross, Datatype, foreignConstraint, Modifier, joinNatural, onJoin, uniqueConstraint, usingJoin } from "./dbStructure.js"
 import { insertQuery, Query, QueryBuilder, removeQuery, selectQuery, updateQuery } from "./query.js"
@@ -244,9 +244,12 @@ export class Handler {
             let a = q.attr;
             for (let i = 0; i < a.length; i++) {
                 const d = a[i];
-                if (d instanceof Attribute || d instanceof AttributeAlias) 
+                if (d instanceof Attribute || d instanceof AttributeAlias)
-                    builder.addCode(d.getString(handler)+" "+ handler.builders.escapeID(d.toString()));
+                    builder.addCode(d.getString(handler) + " " + handler.builders.escapeID(d.toString()));
-                else if (d instanceof Modifier || d instanceof selectQuery || d instanceof Aggregation) {
+                else if (d instanceof Alias) {
+                    builder.append(d.serialize(handler));
+                    builder.addCode(handler.builders.escapeID(d.toString()));
+                } else if (d instanceof Modifier || d instanceof selectQuery || d instanceof Aggregation) {
                     builder.addCode("(");
                     builder.append(d.serialize(handler));
                     builder.addCode(")");
@@ -326,6 +329,8 @@ export class Handler {
                 qb.addCode(s[0].serialize(handler));
                 qb.addCode(" = (");
                 if (s[1] instanceof Attribute || s[1] instanceof AttributeAlias) qb.addCode(s[1].serialize(handler));
+                else if (s[1] instanceof Alias)
+                    qb.addCode(handler.builders.escapeID(s[1].toString()));
                 else if (s[1] instanceof Modifier || s[1] instanceof selectQuery || s[1] instanceof Aggregation) {
                     qb.append(s[1].serialize(handler));
                 } else {
@@ -704,6 +709,8 @@ export class Handler {
         not: (handler: Handler, a: allModifierInput[]): QueryBuilder => {
             let e = a[0];
             if (e instanceof Attribute || e instanceof AttributeAlias) return new QueryBuilder([{ data: "not (" + e.getString(handler) + ")" }])
+            if (e instanceof Alias)
+                return new QueryBuilder([{ data: handler.builders.escapeID(e.toString()) }]);
             if (e instanceof Modifier || e instanceof selectQuery || e instanceof Aggregation) {
                 const builder = new QueryBuilder();
                 builder.addCode("not (");
@@ -720,6 +727,8 @@ export class Handler {
         like: (handler: Handler, a: allModifierInput[]): QueryBuilder => {
             const builder = new QueryBuilder();
             if (a[0] instanceof Attribute || a[0] instanceof AttributeAlias) builder.addCode(a[0].getString());
+            else if (a[0] instanceof Alias)
+                builder.addCode(handler.builders.escapeID(a[0].toString()));
             else if (a[0] instanceof Modifier || a[0] instanceof selectQuery || a[0] instanceof Aggregation) {
                 builder.append(a[0].serialize(handler));
             } else {
@@ -727,6 +736,8 @@ export class Handler {
             }
             builder.addCode(" LIKE ");
             if (a[1] instanceof Attribute || a[1] instanceof AttributeAlias) builder.addCode(a[1].getString());
+            else if (a[1] instanceof Alias)
+                builder.addCode(handler.builders.escapeID(a[1].toString()));
             else if (a[1] instanceof Modifier || a[1] instanceof selectQuery || a[1] instanceof Aggregation) {
                 builder.append(a[1].serialize(handler));
             } else {
@@ -737,6 +748,8 @@ export class Handler {
         regexp: (handler: Handler, a: allModifierInput[]): QueryBuilder => {
             const builder = new QueryBuilder();
             if (a[0] instanceof Attribute || a[0] instanceof AttributeAlias) builder.addCode(a[0].getString());
+            else if (a[0] instanceof Alias)
+                builder.addCode(handler.builders.escapeID(a[0].toString()));
             else if (a[0] instanceof Modifier || a[0] instanceof selectQuery || a[0] instanceof Aggregation) {
                 builder.append(a[0].serialize(handler));
             } else {
@@ -744,6 +757,8 @@ export class Handler {
             }
             builder.addCode(" REGEXP ");
             if (a[1] instanceof Attribute || a[1] instanceof AttributeAlias) builder.addCode(a[1].getString());
+            else if (a[1] instanceof Alias)
+                builder.addCode(handler.builders.escapeID(a[1].toString()));
             else if (a[1] instanceof Modifier || a[1] instanceof selectQuery || a[1] instanceof Aggregation) {
                 builder.append(a[1].serialize(handler));
             } else {
@@ -751,9 +766,11 @@ export class Handler {
             }
             return builder;
         },
-        exists: (handler: Handler, a: allModifierInput[]):QueryBuilder =>{
+        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 Alias)
+                return new QueryBuilder([{ data: handler.builders.escapeID(e.toString()) }]);
             if (e instanceof Modifier || e instanceof selectQuery || e instanceof Aggregation) {
                 const builder = new QueryBuilder();
                 builder.addCode("exists (");
@@ -773,6 +790,8 @@ export class Handler {
             for (let i = 0; i < a.length; i++) {
                 const e = a[i];
                 if (e instanceof Attribute || e instanceof AttributeAlias) builder.addCode(e.getString());
+                else if (e instanceof Alias)
+                    builder.addCode(handler.builders.escapeID(e.toString()));
                 else if (e instanceof Modifier || e instanceof selectQuery || e instanceof Aggregation) {
                     builder.append(e.serialize(handler));
                 } else {
@@ -871,6 +890,8 @@ function joinArg(type: string) {
         for (let i = 0; i < a.length; i++) {
             const d = a[i];
             if (d instanceof Attribute || d instanceof AttributeAlias) builder.addCode(d.getString(handler));
+            else if (d instanceof Alias)
+                builder.addCode(handler.builders.escapeID(d.toString()));
             else if (d instanceof Modifier || d instanceof selectQuery || d instanceof Aggregation) {
                 builder.addCode("(");
                 builder.append(d.serialize(handler));

src/funcs.ts

@@ -1,3 +1,4 @@
+import { Alias } from "./alias.js";
 import { Attribute, Table } from "./db.js";
 import { Aggregation, BooleanModifier, checkConstraint, Datatype, foreignConstraint, joinCross, joinNatural, usingJoin, onJoin, NumberModifier, StringModifier, uniqueConstraint } from "./dbStructure.js";
 import { insertQuery, removeQuery, selectQuery, updateQuery } from "./query.js";
@@ -56,6 +57,9 @@ export const insert = (...attrs: Attribute[]) => new insertQuery(attrs);
 export const update = (table: Table) => new updateQuery(table);
 export const remove = (table: Table) => new removeQuery(table);
 
+//alias
+export const alias = (a: selectElements, name: string) => new Alias(a, name);
+
 //datatypes
 
 export const CHAR = (size: number) => new Datatype("char", [size]);

src/types.ts

@@ -1,12 +1,12 @@
-import { AttributeAlias, TableAlias } from "./alias.js";
+import { Alias, AttributeAlias, TableAlias } from "./alias.js";
 import { Attribute, Table } from "./db.js";
 import { Aggregation, BooleanModifier, Datatype, Joins, Modifier } from "./dbStructure.js";
 import { QueryBuilder, selectQuery } from "./query.js";
 
 export type primaryData = string | number | boolean | null;
-export type allModifierInput = primaryData | Modifier | selectQuery | Attribute | AttributeAlias | Aggregation;
+export type allModifierInput = primaryData | Modifier | selectQuery | Attribute | AttributeAlias | Aggregation | Alias;
 
-export type selectElements = primaryData | Attribute | AttributeAlias | Aggregation | selectQuery
+export type selectElements = primaryData | Attribute | AttributeAlias | Aggregation | selectQuery | Alias;
 export type selectFromElements = TableAlias | Table | Joins | null;
 export type joinElements = Table | Joins;