Add BETWEEN SYMMETRIC.

Pavel Stehule

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 43df7d595c9df30655da6453465ed57a3e67efa7..4fe5e1d6fca6ff6f20a23436c1d6090668d47087 100644 (file)
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1,5 +1,5 @@
 <!--
-$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.255 2005/06/14 21:04:38 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.256 2005/06/14 23:47:39 momjian Exp $
 PostgreSQL documentation
 -->
 
@@ -282,6 +282,12 @@ PostgreSQL documentation
     There is no difference between the two respective forms apart from
     the <acronym>CPU</acronym> cycles required to rewrite the first one
     into the second one internally.
+    <indexterm>
+     <primary>BETWEEN SYMETRIC</primary>
+    </indexterm>
+    <token>BETWEEN SYMMETRIC</> is the same as <literal>BETWEEN</>
+    except there is no requirement that the argument to the left of <literal>AND</> be less than
+    or equal to the argument on the right;  the proper range is automatically determined.
    </para>
 
    <para>

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index c54d6de890413ad839a42991bb1802d1343b6cf8..37ad49eed54ba8c84eaf1025c6529746adebbd65 100644 (file)
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.492 2005/06/08 21:15:28 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.493 2005/06/14 23:47:39 momjian Exp $
  *
  * HISTORY
  *       AUTHOR                        DATE                    MAJOR EVENT
@@ -338,7 +338,7 @@ static void doNegateFloat(Value *v);
 /* ordinary key words in alphabetical order */
 %token <keyword> ABORT_P ABSOLUTE_P ACCESS ACTION ADD AFTER
        AGGREGATE ALL ALSO ALTER ANALYSE ANALYZE AND ANY ARRAY AS ASC
-       ASSERTION ASSIGNMENT AT AUTHORIZATION
+       ASSERTION ASSIGNMENT ASYMMETRIC AT AUTHORIZATION
 
        BACKWARD BEFORE BEGIN_P BETWEEN BIGINT BINARY BIT
        BOOLEAN_P BOTH BY
@@ -399,7 +399,8 @@ static void doNegateFloat(Value *v);
        SAVEPOINT SCHEMA SCROLL SECOND_P SECURITY SELECT SEQUENCE
        SERIALIZABLE SESSION SESSION_USER SET SETOF SHARE
        SHOW SIMILAR SIMPLE SMALLINT SOME STABLE START STATEMENT
-       STATISTICS STDIN STDOUT STORAGE STRICT_P SUBSTRING SYSID
+       STATISTICS STDIN STDOUT STORAGE STRICT_P SUBSTRING SYMMETRIC
+       SYSID
 
        TABLE TABLESPACE TEMP TEMPLATE TEMPORARY THEN TIME TIMESTAMP
        TO TOAST TRAILING TRANSACTION TREAT TRIGGER TRIM TRUE_P
@@ -6333,18 +6334,41 @@ a_expr:         c_expr                                                                  { $$ = $1; }
                                {
                                        $$ = (Node *) makeSimpleA_Expr(AEXPR_OF, "!=", $1, (Node *) $6);
                                }
-                       | a_expr BETWEEN b_expr AND b_expr                      %prec BETWEEN
+                       | a_expr BETWEEN opt_asymmetric b_expr AND b_expr                       %prec BETWEEN
                                {
                                        $$ = (Node *) makeA_Expr(AEXPR_AND, NIL,
-                                               (Node *) makeSimpleA_Expr(AEXPR_OP, ">=", $1, $3),
-                                               (Node *) makeSimpleA_Expr(AEXPR_OP, "<=", $1, $5));
+                                               (Node *) makeSimpleA_Expr(AEXPR_OP, ">=", $1, $4),
+                                               (Node *) makeSimpleA_Expr(AEXPR_OP, "<=", $1, $6));
                                }
-                       | a_expr NOT BETWEEN b_expr AND b_expr          %prec BETWEEN
+                       | a_expr NOT BETWEEN opt_asymmetric b_expr AND b_expr           %prec BETWEEN
                                {
                                        $$ = (Node *) makeA_Expr(AEXPR_OR, NIL,
-                                               (Node *) makeSimpleA_Expr(AEXPR_OP, "<", $1, $4),
-                                               (Node *) makeSimpleA_Expr(AEXPR_OP, ">", $1, $6));
+                                               (Node *) makeSimpleA_Expr(AEXPR_OP, "<", $1, $5),
+                                               (Node *) makeSimpleA_Expr(AEXPR_OP, ">", $1, $7));
                                }
+                               
+                       | a_expr BETWEEN SYMMETRIC b_expr AND b_expr                    %prec BETWEEN
+                               {
+                                       $$ = (Node *) makeA_Expr(AEXPR_OR, NIL,
+                                               (Node *) makeA_Expr(AEXPR_AND, NIL,
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, ">=", $1, $4),
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, "<=", $1, $6)),
+                                               (Node *) makeA_Expr(AEXPR_AND, NIL,
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, ">=", $1, $6),
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, "<=", $1, $4)));                                        
+                               }
+                       | a_expr NOT BETWEEN SYMMETRIC b_expr AND b_expr                %prec BETWEEN
+                               {
+                                       $$ = (Node *) makeA_Expr(AEXPR_AND, NIL,
+                                               (Node *) makeA_Expr(AEXPR_OR, NIL,
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, "<", $1, $5),
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, ">", $1, $7)),
+                                               (Node *) makeA_Expr(AEXPR_OR, NIL,
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, "<", $1, $7),
+                                                   (Node *) makeSimpleA_Expr(AEXPR_OP, ">", $1, $5)));                                 
+                               }
+                               
+                               
                        | a_expr IN_P in_expr
                                {
                                        /* in_expr returns a SubLink or a list of a_exprs */
@@ -6443,6 +6467,11 @@ a_expr:          c_expr                                                                  { $$ = $1; }
                                }
                ;
 
+opt_asymmetric:                ASYMMETRIC                                                                      {}
+                           | /*EMPTY*/                                                         {}
+               ;
+
+
 /*
  * Restricted expressions
  *
@@ -7721,6 +7750,7 @@ unreserved_keyword:
                        | ALTER
                        | ASSERTION
                        | ASSIGNMENT
+                       | ASYMMETRIC
                        | AT
                        | BACKWARD
                        | BEFORE
@@ -7867,6 +7897,7 @@ unreserved_keyword:
                        | STDIN
                        | STDOUT
                        | STORAGE
+                       | SYMMETRIC
                        | SYSID
                        | STRICT_P
                        | TABLESPACE

diff --git a/src/backend/parser/keywords.c b/src/backend/parser/keywords.c
index 359fb845659d47e9f61db8c99befcde2a3b0830d..9296067dfaef3376436d993ab7df48f879eec96c 100644 (file)
--- a/src/backend/parser/keywords.c
+++ b/src/backend/parser/keywords.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/parser/keywords.c,v 1.155 2005/05/07 02:22:47 momjian Exp $
+ *       $PostgreSQL: pgsql/src/backend/parser/keywords.c,v 1.156 2005/06/14 23:47:39 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -49,6 +49,7 @@ static const ScanKeyword ScanKeywords[] = {
        {"asc", ASC},
        {"assertion", ASSERTION},
        {"assignment", ASSIGNMENT},
+       {"asymmetric", ASYMMETRIC},
        {"at", AT},
        {"authorization", AUTHORIZATION},
        {"backward", BACKWARD},
@@ -296,6 +297,7 @@ static const ScanKeyword ScanKeywords[] = {
        {"storage", STORAGE},
        {"strict", STRICT_P},
        {"substring", SUBSTRING},
+       {"symmetric", SYMMETRIC},
        {"sysid", SYSID},
        {"table", TABLE},
        {"tablespace", TABLESPACE},