Add new interfaces for accessing the list of SQL keywords:

sqlite3_keyword_count(), sqlite3_keyword_name(), sqlite3_keyword_check().

FossilOrigin-Name: 7dd34e3776fed90a49344d54a1b68bb59f7957b5a8a1a367087b7cafb63111c1

3 files changed, 54 insertions, 69 deletions

diff --git a/src/main.c b/src/main.c
index 99e3e6f97..442067a14 100644
--- a/src/main.c
+++ b/src/main.c
@@ -3861,24 +3861,6 @@ int sqlite3_test_control(int op, ...){
       break;
     }
 
-#ifdef SQLITE_N_KEYWORD
-    /* sqlite3_test_control(SQLITE_TESTCTRL_ISKEYWORD, const char *zWord)
-    **
-    ** If zWord is a keyword recognized by the parser, then return the
-    ** number of keywords.  Or if zWord is not a keyword, return 0.
-    ** 
-    ** This test feature is only available in the amalgamation since
-    ** the SQLITE_N_KEYWORD macro is not defined in this file if SQLite
-    ** is built using separate source files.
-    */
-    case SQLITE_TESTCTRL_ISKEYWORD: {
-      const char *zWord = va_arg(ap, const char*);
-      int n = sqlite3Strlen30(zWord);
-      rc = (sqlite3KeywordCode((u8*)zWord, n)!=TK_ID) ? SQLITE_N_KEYWORD : 0;
-      break;
-    }
-#endif 
-
     /*   sqlite3_test_control(SQLITE_TESTCTRL_LOCALTIME_FAULT, int onoff);
     **
     ** If parameter onoff is non-zero, configure the wrappers so that all
diff --git a/src/shell.c.in b/src/shell.c.in
index c5cb7ec16..c0e5c7a75 100644
--- a/src/shell.c.in
+++ b/src/shell.c.in
@@ -774,46 +774,12 @@ static void appendText(ShellText *p, char const *zAppend, char quote){
 ** Return '"' if quoting is required.  Return 0 if no quoting is required.
 */
 static char quoteChar(const char *zName){
-  /* All SQLite keywords, in alphabetical order */
-  static const char *azKeywords[] = {
-    "ABORT", "ACTION", "ADD", "AFTER", "ALL", "ALTER", "ANALYZE", "AND", "AS",
-    "ASC", "ATTACH", "AUTOINCREMENT", "BEFORE", "BEGIN", "BETWEEN", "BY",
-    "CASCADE", "CASE", "CAST", "CHECK", "COLLATE", "COLUMN", "COMMIT",
-    "CONFLICT", "CONSTRAINT", "CREATE", "CROSS", "CURRENT_DATE",
-    "CURRENT_TIME", "CURRENT_TIMESTAMP", "DATABASE", "DEFAULT", "DEFERRABLE",
-    "DEFERRED", "DELETE", "DESC", "DETACH", "DISTINCT", "DO", "DROP", "EACH",
-    "ELSE", "END", "ESCAPE", "EXCEPT", "EXCLUSIVE", "EXISTS", "EXPLAIN",
-    "FAIL", "FOR", "FOREIGN", "FROM", "FULL", "GLOB", "GROUP", "HAVING", "IF",
-    "IGNORE", "IMMEDIATE", "IN", "INDEX", "INDEXED", "INITIALLY", "INNER",
-    "INSERT", "INSTEAD", "INTERSECT", "INTO", "IS", "ISNULL", "JOIN", "KEY",
-    "LEFT", "LIKE", "LIMIT",
-    "MATCH", "NATURAL", "NO", "NOT", "NOTHING", "NOTNULL",
-    "NULL", "OF", "OFFSET", "ON", "OR", "ORDER", "OUTER", "PLAN", "PRAGMA",
-    "PRIMARY", "QUERY", "RAISE", "RECURSIVE", "REFERENCES", "REGEXP",
-    "REINDEX", "RELEASE", "RENAME", "REPLACE", "RESTRICT", "RIGHT",
-    "ROLLBACK", "ROW", "SAVEPOINT", "SELECT", "SET", "TABLE", "TEMP",
-    "TEMPORARY", "THEN", "TO", "TRANSACTION", "TRIGGER", "UNION", "UNIQUE",
-    "UPDATE", "USING", "VACUUM", "VALUES", "VIEW", "VIRTUAL", "WHEN", "WHERE",
-    "WITH", "WITHOUT",
-  };
-  int i, lwr, upr, mid, c;
+  int i;
   if( !isalpha((unsigned char)zName[0]) && zName[0]!='_' ) return '"';
   for(i=0; zName[i]; i++){
     if( !isalnum((unsigned char)zName[i]) && zName[i]!='_' ) return '"';
   }
-  lwr = 0;
-  upr = sizeof(azKeywords)/sizeof(azKeywords[0]) - 1;
-  while( lwr<=upr ){
-    mid = (lwr+upr)/2;
-    c = sqlite3_stricmp(azKeywords[mid], zName);
-    if( c==0 ) return '"';
-    if( c<0 ){
-      lwr = mid+1;
-    }else{
-      upr = mid-1;
-    }
-  }
-  return 0;
+  return sqlite3_keyword_check(zName, i) ? '"' : 0;
 }
 
 /*
@@ -7497,9 +7463,6 @@ static int do_meta_command(char *zLine, ShellState *p){
       { "byteorder",          SQLITE_TESTCTRL_BYTEORDER,     ""                   },
     /*{ "fault_install",      SQLITE_TESTCTRL_FAULT_INSTALL, ""                }, */
       { "imposter",           SQLITE_TESTCTRL_IMPOSTER,   "SCHEMA ON/OFF ROOTPAGE"},
-#ifdef SQLITE_N_KEYWORD
-      { "iskeyword",          SQLITE_TESTCTRL_ISKEYWORD,     "IDENTIFIER"         },
-#endif
       { "localtime_fault",    SQLITE_TESTCTRL_LOCALTIME_FAULT,"BOOLEAN"           },
       { "never_corrupt",      SQLITE_TESTCTRL_NEVER_CORRUPT, "BOOLEAN"            },
       { "optimizations",      SQLITE_TESTCTRL_OPTIMIZATIONS, "DISABLE-MASK"       },
@@ -7611,17 +7574,6 @@ static int do_meta_command(char *zLine, ShellState *p){
           }
           break;
 
-        /* sqlite3_test_control(int, char *) */
-#ifdef SQLITE_N_KEYWORD
-        case SQLITE_TESTCTRL_ISKEYWORD:
-          if( nArg==3 ){
-            const char *opt = azArg[2];
-            rc2 = sqlite3_test_control(testctrl, opt);
-            isOk = 1;
-          }
-          break;
-#endif
-
         case SQLITE_TESTCTRL_IMPOSTER:
           if( nArg==5 ){
             rc2 = sqlite3_test_control(testctrl, p->db,
diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 02dc8944b..4d84bf3eb 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -7016,7 +7016,7 @@ int sqlite3_test_control(int op, ...);
 #define SQLITE_TESTCTRL_ALWAYS                  13
 #define SQLITE_TESTCTRL_RESERVE                 14
 #define SQLITE_TESTCTRL_OPTIMIZATIONS           15
-#define SQLITE_TESTCTRL_ISKEYWORD               16
+#define SQLITE_TESTCTRL_ISKEYWORD               16  /* NOT USED */
 #define SQLITE_TESTCTRL_SCRATCHMALLOC           17  /* NOT USED */
 #define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
 #define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
@@ -7031,6 +7031,57 @@ int sqlite3_test_control(int op, ...);
 #define SQLITE_TESTCTRL_LAST                    26  /* Largest TESTCTRL */
 
 /*
+** CAPI3REF: SQL Keyword Checking
+**
+** These routines provide access to the set of SQL language keywords 
+** recognized by SQLite.  Applications can uses these routines to determine
+** whether or not a specific identifier needs to be escaped (for example,
+** by enclosing in double-quotes) so as not to confuse the parser.
+**
+** The sqlite3_keyword_count() interface returns the number of distinct
+** keywords understood by SQLite.
+**
+** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and
+** makes *Z point to that keyword expressed as UTF8 and writes the number
+** of bytes in the keyword into *L.  The string that *Z points to is not
+** zero-terminated.  The sqlite3_keyword_name(N,Z,L) routine returns
+** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
+** or L are NULL or invalid pointers then calls to
+** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
+**
+** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
+** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
+** if it is and zero if not.
+**
+** The parser used by SQLite is forgiving.  It is often possible to use
+** a keyword as an identifier as long as such use does not result in a
+** parsing ambiguity.  For example, the statement
+** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
+** creates a new table named "BEGIN" with three columns named
+** "REPLACE", "PRAGMA", and "END".  Nevertheless, best practice is to avoid
+** using keywords as identifiers.  Common techniques used to avoid keyword
+** name collisions include:
+** <ul>
+** <li> Put all indentifier names inside double-quotes.  This is the official
+**      SQL way to escape identifier names.
+** <li> Put identifier names inside &#91;...&#93;.  This is not standard SQL,
+**      but it is what SQL Server does and so lots of programmers use this
+**      technique.
+** <li> Begin every identifier with the letter "Z" as no SQL keywords start
+**      with "Z".
+** <li> Include a digit somewhere in every identifier name.
+** </ul>
+**
+** Note that the number of keywords understood by SQLite can depend on
+** compile-time options.  For example, "VACUUM" is not a keyword if
+** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option.  Also,
+** new keywords may be added to future releases of SQLite.
+*/
+int sqlite3_keyword_count(void);
+int sqlite3_keyword_name(int,const char**,int*);
+int sqlite3_keyword_check(const char*,int);
+
+/*
 ** CAPI3REF: SQLite Runtime Status
 **
 ** ^These interfaces are used to retrieve runtime status information