readme: update readme with sql examples

Added the test covered examples of using SQL from connector.
Updated config.lua by creation the space for testing SQL from
example.

Follows up #62

Author: vr009

README.md

@@ -282,6 +282,24 @@ func main() {
 	log.Println("Error", err)
 	log.Println("Code", resp.Code)
 	log.Println("Data", resp.Data)
+
+	// prepare map for sql bind
+	sqlBind := map[string]interface{}{
+        "id":   1,
+        "name": "test",
+	}
+	// insert data using sql query
+	resp, err = client.Execute("INSERT INTO SQL_TEST VALUES (:id, :name);", sqlBind)
+	log.Println("Execute Error", err)
+	log.Println("Execute Code", resp.Code)
+	log.Println("Execute Data", resp.Data)
+
+	sqlBind = map[string]interface{}{"name": "test"}
+	// select data using sql query
+	resp, err = client.Execute("SELECT id, name FROM SQL_TEST WHERE name=:name", sqlBind)
+	log.Println("Execute Error", err)
+	log.Println("Execute Code", resp.Code)
+	log.Println("Execute Data", resp.Data)
 }
 ```
 

config.lua

@@ -40,6 +40,22 @@ box.once("init", function()
     })
     st:truncate()
 
+    local sp = box.schema.space.create('SQL_TEST', {
+        id = 515,
+        temporary = true,
+        if_not_exists = true,
+        field_count = 2,
+        format = {
+            {name = "ID", type = "unsigned"},
+            {name = "NAME", type = "string"},
+        },
+    })
+    sp:create_index('primary', {
+        type = 'tree',
+        parts = {1, 'uint'},
+        unique = true,
+        if_not_exists = true,
+    })
     --box.schema.user.grant('guest', 'read,write,execute', 'universe')
     box.schema.func.create('box.info')
     box.schema.func.create('simple_incr')
@@ -49,6 +65,7 @@ box.once("init", function()
     box.schema.user.grant('test', 'execute', 'universe')
     box.schema.user.grant('test', 'read,write', 'space', 'test')
     box.schema.user.grant('test', 'read,write', 'space', 'schematest')
+    box.schema.user.grant('test', 'read,write', 'space', 'SQL_TEST')
 end)
 
 local function simple_incr(a)

example_test.go

@@ -168,6 +168,24 @@ func Example() {
 	fmt.Println("Eval Code", resp.Code)
 	fmt.Println("Eval Data", resp.Data)
 
+	// prepare map for sql bind
+	sqlBind := map[string]interface{}{
+		"id":   1,
+		"name": "test",
+	}
+	// insert data using sql query
+	resp, err = client.Execute("INSERT INTO SQL_TEST VALUES (:id, :name);", sqlBind)
+	fmt.Println("Execute Error", err)
+	fmt.Println("Execute Code", resp.Code)
+	fmt.Println("Execute Data", resp.Data)
+
+	sqlBind = map[string]interface{}{"name": "test"}
+	// select data using sql query
+	resp, err = client.Execute("SELECT id, name FROM SQL_TEST WHERE name=:name", sqlBind)
+	fmt.Println("Execute Error", err)
+	fmt.Println("Execute Code", resp.Code)
+	fmt.Println("Execute Data", resp.Data)
+
 	resp, err = client.Replace("test", &Tuple{Id: 11, Msg: "test", Name: "eleven"})
 	resp, err = client.Replace("test", &Tuple{Id: 12, Msg: "test", Name: "twelve"})
 
@@ -215,6 +233,12 @@ func Example() {
 	// Eval Error <nil>
 	// Eval Code 0
 	// Eval Data [3]
+	// Execute Error <nil>
+	// Execute Code 0
+	// Execute Data []
+	// Execute Error <nil>
+	// Execute Code 0
+	// Execute Data [[1 test]]
 	// Fut 0 Error <nil>
 	// Fut 0 Data [{{} 12 test twelve} {{} 11 test eleven}]
 	// Fut 1 Error <nil>