update readme

Author: niquola

README.md

@@ -2,6 +2,7 @@
 
 [![Build Status](https://travis-ci.org/niquola/jsquery.svg)](https://travis-ci.org/niquola/jsquery)
 
+
 `Jsquery` is PostgreSQL extension,
 which provides advanced query language for jsonb documents.
 
@@ -15,6 +16,7 @@ Features:
 * indexes support
 * hinting support
 
+
 Jsquery implemented as datatype `jsquery` and operator `@@`.
 
 Examples:
@@ -51,9 +53,7 @@ select 'a1."12222" < 111'::jsquery;
 
 ## Documentation
 
-* [Getting Started](doc/intro.md)
-* [Syntax](doc/syntax.md)
-* [Operators](doc/operators.md)
+* [Syntax](doc/intro.md)
 * [Indexes](doc/indexes.md)
 * [Optimizer](doc/optimiser.md)
 

doc/intro.md

@@ -26,14 +26,99 @@ For example if we are looking for:
 }
 ```
 
-the expresion is:
+the expression is:
 
 ```
 user.name = 'diego'
 ```
 
-Sevral expressions could be connected using `AND` & `OR` operators:
+Sevral expressions could be connected using boolean `AND` & `OR` operators:
 
 ```
 user.name = 'diego' AND site.url = 'diego.com'
 ```
+
+Expression could be negated with `NOT` operator:
+
+```
+NOT user.name = 'diego'
+```
+
+JSON value could be one following types:
+
+* array
+* numeric
+* object
+* string
+* boolean
+
+You can check type using `is` operator:
+
+```
+user.name is array
+user.name is numeric
+user.name is object
+user.name is string
+user.name is boolean
+```
+
+For all types you `=` (equality) operator is defined:
+
+```
+user.roles = ["admin","root"]
+user.age = 3
+user.active = true
+user.address = {city: "SPb"}
+user.name = "diego"
+```
+
+For numerics there are expected comparison operators:
+
+```
+x > 1 AND x < 10
+x >= 1 AND x <= 10
+```
+
+To check that scalar value belongs to some list:
+
+```sql
+select '{a: 2}'::jsonb @@ 'a IN (1,2,5)';
+```
+
+For arrays there are convenient operators:
+
+```sql
+-- overlap
+select '{"a": {"b": [1,2,3]}}'::jsonb @@ 'a.b && [1,2,5]';
+
+-- contains
+select '{"a": {"b": [1,2,3]}}'::jsonb @@ 'a.b @> [1,2]';
+
+-- contained
+select '{"a": {"b": [1,2,3]}}'::jsonb @@ 'a.b <@ [1,2,3,4,5]'
+```
+
+If you just want to check that some path exists in json document use `=*`:
+
+select '{"a": {"b": [1,2,3]}}'::jsonb @@ 'a.b = *'
+
+
+Path expression supports wild cards:
+
+`#` - any alement of array
+`%` - any key in object
+`*` - any path
+
+```sql
+select '{a: {b: {c: 1}}}'::jsonb @@ '*.c = 1'
+select '{a: {b: {c: 1}}}'::jsonb @@ 'a.%.c = 1'
+select '{a: {b: [1,2]}}'::jsonb @@ 'a.b.# = 1'
+```
+
+jsquery expression could be expressed recursively using `()`:
+
+```
+address(city = "SPB" AND street = "Nevskiy")
+```
+
+This means eval `city = "SPB" AND street = "Nevskiy"` expression in context of `address` attribute.