operand count added

Author: wolfram77

README.md

@@ -35,6 +35,7 @@ sql.matchTsquery('columns', ['total', 'fat']);
 | [selectTsquery]     | Generates SQL command for SELECT with tsquery.
 | [matchTsquery]      | Generates SQL query for matching words with tsquery.
 | [OPERATORS]         | Set of operators in SQL. {field}
+| [OPERAND_COUNT]     | Number of operands used with an SQL operator. {field}
 
 <br>
 <br>
@@ -49,4 +50,6 @@ sql.matchTsquery('columns', ['total', 'fat']);
 [tableExists]: https://github.com/nodef/extra-sql/wiki/tableExists
 [selectTsquery]: https://github.com/nodef/extra-sql/wiki/selectTsquery
 [matchTsquery]: https://github.com/nodef/extra-sql/wiki/matchTsquery
+[OPERATORS]: https://github.com/nodef/extra-sql/wiki/OPERATORS
+[OPERAND_COUNT]: https://github.com/nodef/extra-sql/wiki/OPERAND_COUNT
 [SQL]: https://en.wikipedia.org/wiki/SQL

index.js

@@ -14,6 +14,22 @@ const OPERATORS = new Set([
 	'ALL', 'AND', 'ANY', 'BETWEEN', 'EXISTS', 'IN', 'IN', 'LIKE', 'NOT', 'OR', 'SOME'
 ]);
 
+/**
+ * Number of operands used with an SQL operator.
+ */
+const OPERAND_COUNT = new Map([
+  // arithmetic operators
+  ['+', 2], ['-', 2], ['*', 2], ['/', 2], ['%', 2],
+  // bitwise operators
+  ['&', 2], ['|', 2], ['^', 2],
+  // comparision operators
+  ['=', 2], ['>', 2], ['<', 2], ['>=', 2], ['<=', 2], ['<>', 2],
+  // compound operators
+  ['+=', 2], ['-=', 2], ['*=', 2], ['/=', 2], ['%=', 2], ['&=', 2], ['^=', 2], ['|=', 2],
+  // logical operators
+  ['ALL', 2], ['AND', 2], ['ANY', 2], ['BETWEEN', 3], ['EXISTS', 1], ['IN', 2], ['LIKE', 2], ['NOT', 1], ['OR', 2], ['SOME', 2]
+]);
+
 
 /**
  * Generates SQL command for CREATE TABLE.
@@ -220,6 +236,7 @@ function matchTsquery(tab, wrds, tsv='"tsvector"', opt={}) {
   return z;
 }
 exports.OPERATORS = OPERATORS;
+exports.OPERAND_COUNT = OPERAND_COUNT;
 exports.createTable = createTable;
 exports.createIndex = createIndex;
 exports.createView = createView;

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "extra-sql",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "description": "SQL is designed for managing or stream processing data in an RDBMS.",
   "main": "index.js",
   "scripts": {