From 6fc74eb8f1a5fd3b4ee500c974bc16f2881db8bc Mon Sep 17 00:00:00 2001
From: ygrek <ygrek@autistici.org>
Date: Sun, 19 Jul 2009 11:41:36 +0300
Subject: [PATCH] sql: CASE ... END, TODO more polymorphic `Func

---
 src/sql_lexer.mll  | 5 +++++
 src/sql_parser.mly | 7 +++++++
 src/test.ml        | 3 +++
 3 files changed, 15 insertions(+)

diff --git a/src/sql_lexer.mll b/src/sql_lexer.mll
index 74d0094..6f784b7 100644
--- a/src/sql_lexer.mll
+++ b/src/sql_lexer.mll
@@ -101,6 +101,11 @@ let keywords =
    "first",FIRST;
    "column",COLUMN;
    "like", LIKE;
+   "case", CASE;
+   "when", WHEN;
+   "then", THEN;
+   "else", ELSE;
+   "end", END;
   ] in (* more *)
   let all token l = k := !k @ List.map (fun x -> x,token) l in
   all (FUNCTION T.Int) ["max"; "min"; "length"; "random";"count";"sum";"avg"];
diff --git a/src/sql_parser.mly b/src/sql_parser.mly
index b1ff3ed..b317295 100644
--- a/src/sql_parser.mly
+++ b/src/sql_parser.mly
@@ -49,6 +49,7 @@
        PRECISION UNSIGNED ZEROFILL VARYING CHARSET NATIONAL ASCII UNICODE COLLATE BINARY CHARACTER
        DATETIME_FUNC DATE TIME TIMESTAMP ALTER ADD COLUMN CASCADE RESTRICT DROP
        GLOBAL LOCAL VALUE REFERENCES CHECK CONSTRAINT IGNORED AFTER INDEX FULLTEXT FIRST
+       CASE WHEN THEN ELSE END
 %token NUM_BINARY_OP PLUS MINUS COMPARISON_OP
 %token T_INTEGER T_BLOB T_TEXT T_FLOAT T_BOOLEAN T_DATETIME
 
@@ -309,7 +310,13 @@ expr:
     | expr TEST_NULL { $1 }
     | expr mnot(BETWEEN) expr AND expr { `Func (Int,[$1;$3;$5]) }
     | mnot(EXISTS) LPAREN select=select_stmt RPAREN { `Func (Bool,params_of select) }
+    | CASE e1=expr? branches=nonempty_list(case_branch) e2=preceded(ELSE,expr)? END 
+      {
+        let l = function None -> [] | Some x -> [x] in
+        `Func (Any,l e1 @ List.flatten branches @ l e2)
+      }
 
+case_branch: WHEN e1=expr THEN e2=expr { [e1;e2] }
 like: LIKE | LIKE_OP { }
 
 datetime_value: | DATETIME_FUNC | DATETIME_FUNC LPAREN INTEGER? RPAREN { `Value Datetime }
diff --git a/src/test.ml b/src/test.ml
index b9f10af..eef1e01 100644
--- a/src/test.ml
+++ b/src/test.ml
@@ -54,6 +54,9 @@ let test () =
      [p "name" Text];
   tt "insert or replace into test values (2,?,?)" [] [param,Text; param,Text;];
   tt "replace into test values (2,?,?)" [] [param,Text; param,Text;];
+  tt "select str, case when id > @id then name when id < @id then 'qqq' else @def end as q from test"
+    [attr "str" Text; attr "q" Any] (* FIXME `Func *)
+    [p "id" Int; p "id" Int; p "def" Any];
   wrong "insert into test values (1,2)";
   wrong "insert into test (str,name) values (1,'str','name')";
   ()
-- 
2.11.4.GIT