X-Git-Url: http://git.kpe.io/?p=clsql.git;a=blobdiff_plain;f=sql%2Fexpressions.lisp;h=8b6167ba2c71f22ba288835e0699a04f554d9431;hp=983d4a526bb5667e1eb6fa17f2c6090c15f93823;hb=b50166ae0ba2bc09a9094c0e675ec92010b7293e;hpb=912e2a813087be98c0ede7cbe0c62ab7f7633706

diff --git a/sql/expressions.lisp b/sql/expressions.lisp
index 983d4a5..8b6167b 100644
--- a/sql/expressions.lisp
+++ b/sql/expressions.lisp
@@ -249,6 +249,10 @@
   (declare (ignore sql))
   nil)
 
+(defmethod collect-table-refs ((sql list))
+  (loop for i in sql
+        appending (listify (collect-table-refs i))))
+
 (defmethod collect-table-refs ((sql sql-ident-attribute))
   (let ((qual (slot-value sql 'qualifier)))
     (when qual
@@ -286,6 +290,9 @@
     sql
     `(make-instance 'sql-ident-table :name ',name :table-alias ',alias)))
 
+(defmethod collect-table-refs ((sql sql-ident-table))
+  (list sql))
+
 (defmethod output-sql ((expr sql-ident-table) database)
   (with-slots (name alias) expr
     (flet ((p (s) ;; the etypecase is in sql-escape too
@@ -1182,3 +1189,51 @@ uninclusive, and the args from that keyword to the end."
       (%sql-expression (flatten-id name))
       )))
 
+(defun %clsql-subclauses (clauses)
+  "a helper for dealing with lists of sql clauses"
+  (loop for c in clauses
+        when c
+        collect (typecase c
+                  (string (clsql-sys:sql-expression :string c))
+                  (T c))))
+
+(defun clsql-ands (clauses)
+  "Correctly creates a sql 'and' expression for the clauses
+    ignores any nil clauses
+    returns a single child expression if there is only one
+    returns an 'and' expression if there are many
+    returns nil if there are no children"
+  (let ((ex (%clsql-subclauses clauses)))
+    (when ex
+      (case (length ex)
+        (1 (first ex))
+        (t (apply #'clsql-sys:sql-and ex))))))
+
+(defun clsql-and (&rest clauses)
+  "Correctly creates a sql 'and' expression for the clauses
+    ignores any nil clauses
+    returns a single child expression if there is only one
+    returns an 'and' expression if there are many
+    returns nil if there are no children"
+  (clsql-ands clauses))
+
+(defun clsql-ors (clauses)
+  "Correctly creates a sql 'or' expression for the clauses
+    ignores any nil clauses
+    returns a single child expression if there is only one
+    returns an 'or' expression if there are many
+    returns nil if there are no children"
+  (let ((ex (%clsql-subclauses clauses)))
+    (when ex
+      (case (length ex)
+        (1 (first ex))
+        (t (apply #'clsql-sys:sql-or ex))))))
+
+(defun clsql-or (&rest clauses)
+  "Correctly creates a sql 'or' expression for the clauses
+    ignores any nil clauses
+    returns a single child expression if there is only one
+    returns an 'or' expression if there are many
+    returns nil if there are no children"
+  (clsql-ors clauses))
+