From 461911889a3cea08c731e48bf1aa3a5b572993f7 Mon Sep 17 00:00:00 2001
From: go-jet <zer0.sub@protonmail.com>
Date: Mon, 1 Jul 2019 13:18:39 +0200
Subject: [PATCH] Add LOCK statement wiki.

---
 wiki/LOCK.md     | 45 +++++++++++++++++++++++++++++++++++++++++++++
 wiki/SELECT.md   | 18 +++++++++++++++---
 wiki/_Sidebar.md |  4 +++-
 3 files changed, 63 insertions(+), 4 deletions(-)
 create mode 100644 wiki/LOCK.md

diff --git a/wiki/LOCK.md b/wiki/LOCK.md
new file mode 100644
index 0000000..b86e849
--- /dev/null
+++ b/wiki/LOCK.md
@@ -0,0 +1,45 @@
+
+LOCK statement obtains a table-level lock, waiting if necessary for any conflicting locks to be released.
+More about LOCK statement in PostgreSQL: https://www.postgresql.org/docs/11/sql-lock.html  
+
+Following clauses are supported:
+- IN(mode) - mode specifies which locks this lock conflicts with.  
+Mode can be: 
+    - jet.LOCK_ACCESS_SHARE          
+    - jet.LOCK_ROW_SHARE             
+    - jet.LOCK_ROW_EXCLUSIVE         
+    - jet.LOCK_SHARE_UPDATE_EXCLUSIVE
+    - jet.LOCK_SHARE                 
+    - jet.LOCK_SHARE_ROW_EXCLUSIVE   
+    - jet.LOCK_EXCLUSIVE             
+    - jet.LOCK_ACCESS_EXCLUSIVE      
+- NOWAIT() - locked table should not wait for any conflicting locks to be released. If the specified lock(s) 
+cannot be acquired immediately without waiting, the transaction is aborted.
+
+## Example
+
+
+```
+lockStmt := Address.
+        LOCK().
+        IN(jet.LOCK_ACCESS_SHARE).
+        NOWAIT()
+```
+
+Debug SQL of above statement:
+
+```sql
+LOCK TABLE dvds.address IN ACCESS SHARE MODE NOWAIT;
+```
+
+### Execute statement
+
+To execute update statement and get sql.Result:
+
+```
+res, err := lockStmt.Exec(db)
+```
+
+Use `ExecContext` to provide context object to execution.
+
+ 
\ No newline at end of file
diff --git a/wiki/SELECT.md b/wiki/SELECT.md
index e903190..0b99e6b 100644
--- a/wiki/SELECT.md
+++ b/wiki/SELECT.md
@@ -123,15 +123,27 @@ SQL:
 OFFSET 11
 ```
 
-##### 9. FOR clause
+##### 9. FOR clause 
+
+Lock mode can be:
+- jet.UPDATE()       
+- jet.NO_KEY_UPDATE()
+- jet.SHARE()      
+- jet.KEY_SHARE()    
+
+Lock mode has following clauses:
+- NOWAIT()
+- SKIP_LOCKED()
+
 ```
 Go:
-.FOR(jet.NO_KEY_UPDATE)
+.FOR(jet.NO_KEY_UPDATE().SKIP_LOCKED())
 
 SQL:
-FOR NO KEY UPDATE
+FOR NO KEY UPDATE SKIP LOCKED
 ```
 
+
 ### Two forms of select statements in Jet
 
 #### 1. Classical select statement
diff --git a/wiki/_Sidebar.md b/wiki/_Sidebar.md
index ef6ac47..cc97acd 100644
--- a/wiki/_Sidebar.md
+++ b/wiki/_Sidebar.md
@@ -1,6 +1,7 @@
 
 * [Installation](https://github.com/go-jet/jet/wiki/Installation)
 * [Generator](https://github.com/go-jet/jet/wiki/Generator)
+* [Model data](https://github.com/go-jet/jet/wiki/Model-data.md)
 * [Writing SQL in Go]() 
     * [Expressions](https://github.com/go-jet/jet/wiki/Expressions)
     * [Statements](https://github.com/go-jet/jet/wiki/Statements)
@@ -8,4 +9,5 @@
         * [INSERT](https://github.com/go-jet/jet/wiki/INSERT)
         * [UPDATE](https://github.com/go-jet/jet/wiki/UPDATE)
         * [DELETE](https://github.com/go-jet/jet/wiki/DELETE)
-        * [LOCK](https://github.com/go-jet/jet/wiki/LOCK)
\ No newline at end of file
+        * [LOCK](https://github.com/go-jet/jet/wiki/LOCK)
+* [Execution]()
\ No newline at end of file