Allow hints to be placed anywhere in query

[pghintplan/pg_hint_plan.git] / pg_hint_plan.c

diff --git a/pg_hint_plan.c b/pg_hint_plan.c
index 5a044b8..0852f56 100644 (file)
--- a/pg_hint_plan.c
+++ b/pg_hint_plan.c
@@ -530,6 +530,7 @@ static int  pg_hint_plan_parse_message_level = INFO;
 static int     pg_hint_plan_debug_message_level = LOG;
 /* Default is off, to keep backward compatibility. */
 static bool    pg_hint_plan_enable_hint_table = false;
+static bool    pg_hint_plan_hints_anywhere = false;
 
 static int plpgsql_recurse_level = 0;          /* PLpgSQL recursion level            */
 static int recurse_level = 0;          /* recursion level incl. direct SPI calls */
@@ -701,6 +702,17 @@ _PG_init(void)
                                                         assign_enable_hint_table,
                                                         NULL);
 
+       DefineCustomBoolVariable("pg_hint_plan.hints_anywhere",
+                                                        "Read hints from anywhere in a query.",
+                                                        "This option lets pg_hint_plan ignore syntax so be cautious for false reads.",
+                                                        &pg_hint_plan_hints_anywhere,
+                                                        false,
+                                                        PGC_USERSET,
+                                                        0,
+                                                        NULL,
+                                                        NULL,
+                                                        NULL);
+
        EmitWarningsOnPlaceholders("pg_hint_plan");
 
        /* Install hooks. */
@@ -1881,33 +1893,35 @@ get_hints_from_comment(const char *p)
        hint_head = strstr(p, HINT_START);
        if (hint_head == NULL)
                return NULL;
-       for (;p < hint_head; p++)
+       if (!pg_hint_plan_hints_anywhere)
        {
-               /*
-                * Allow these characters precedes hint comment:
-                *   - digits
-                *   - alphabets which are in ASCII range
-                *   - space, tabs and new-lines
-                *   - underscores, for identifier
-                *   - commas, for SELECT clause, EXPLAIN and PREPARE
-                *   - parentheses, for EXPLAIN and PREPARE
-                *
-                * Note that we don't use isalpha() nor isalnum() in ctype.h here to
-                * avoid behavior which depends on locale setting.
-                */
-               if (!(*p >= '0' && *p <= '9') &&
-                       !(*p >= 'A' && *p <= 'Z') &&
-                       !(*p >= 'a' && *p <= 'z') &&
-                       !isspace(*p) &&
-                       *p != '_' &&
-                       *p != ',' &&
-                       *p != '(' && *p != ')')
-                       return NULL;
+               for (;p < hint_head; p++)
+               {
+                       /*
+                        * Allow these characters precedes hint comment:
+                        *   - digits
+                        *   - alphabets which are in ASCII range
+                        *   - space, tabs and new-lines
+                        *   - underscores, for identifier
+                        *   - commas, for SELECT clause, EXPLAIN and PREPARE
+                        *   - parentheses, for EXPLAIN and PREPARE
+                        *
+                        * Note that we don't use isalpha() nor isalnum() in ctype.h here to
+                        * avoid behavior which depends on locale setting.
+                        */
+                       if (!(*p >= '0' && *p <= '9') &&
+                               !(*p >= 'A' && *p <= 'Z') &&
+                               !(*p >= 'a' && *p <= 'z') &&
+                               !isspace(*p) &&
+                               *p != '_' &&
+                               *p != ',' &&
+                               *p != '(' && *p != ')')
+                               return NULL;
+               }
        }
 
-       len = strlen(HINT_START);
-       head = (char *) p;
-       p += len;
+       head = (char *)hint_head;
+       p = head + strlen(HINT_START);
        skip_space(p);
 
        /* find hint end keyword. */
@@ -2921,7 +2935,7 @@ get_current_hint_string(Query *query, const char *query_str,
 
        if (debug_level > 1)
        {
-               if (debug_level == 1 && query_str && debug_query_string &&
+               if (debug_level == 2 && query_str && debug_query_string &&
                        strcmp(query_str, debug_query_string))
                        ereport(pg_hint_plan_debug_message_level,
                                        (errmsg("hints in comment=\"%s\"",
@@ -3570,7 +3584,7 @@ restrict_indexes(PlannerInfo *root, ScanMethodHint *hint, RelOptInfo *rel,
                pfree(indexname);
        }
 
-       if (debug_level == 1)
+       if (debug_level > 0)
        {
                StringInfoData  rel_buf;
                char *disprelname = "";