Remove unused fields from the Parse object.  Documentation and formatting
improvements on data structure definitions.

FossilOrigin-Name: 431556cac0b2c86d7f6a60412ff1023feeaafedf
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 856e878..4e00ad0 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -2072,13 +2072,13 @@
 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
 ** "Select Flag".
 */
-#define SF_Distinct        0x0001  /* Output should be DISTINCT */
-#define SF_Resolved        0x0002  /* Identifiers have been resolved */
-#define SF_Aggregate       0x0004  /* Contains aggregate functions */
-#define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
-#define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
-#define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
-#define SF_UseSorter       0x0040  /* Sort using a sorter */
+#define SF_Distinct        0x01  /* Output should be DISTINCT */
+#define SF_Resolved        0x02  /* Identifiers have been resolved */
+#define SF_Aggregate       0x04  /* Contains aggregate functions */
+#define SF_UsesEphemeral   0x08  /* Uses the OpenEphemeral opcode */
+#define SF_Expanded        0x10  /* sqlite3SelectExpand() called on this */
+#define SF_HasTypeInfo     0x20  /* FROM subqueries have Table metadata */
+#define SF_UseSorter       0x40  /* Sort using a sorter */
 
 
 /*
@@ -2193,10 +2193,8 @@
   char *zErrMsg;       /* An error message */
   Vdbe *pVdbe;         /* An engine for executing database bytecode */
   u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
-  u8 nameClash;        /* A permanent table name clashes with temp table name */
   u8 checkSchema;      /* Causes schema cookie check after an error */
   u8 nested;           /* Number of nested calls to the parser/code generator */
-  u8 parseError;       /* True after a parsing error.  Ticket #1794 */
   u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
   u8 nTempInUse;       /* Number of aTempReg[] currently checked out */
   int aTempReg[8];     /* Holding area for temporary registers */
@@ -2209,8 +2207,8 @@
   int ckBase;          /* Base register of data during check constraints */
   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
-  u8 nColCache;        /* Number of entries in the column cache */
-  u8 iColCache;        /* Next entry of the cache to replace */
+  u8 nColCache;        /* Number of entries in aColCache[] */
+  u8 iColCache;        /* Next entry in aColCache[] to replace */
   struct yColCache {
     int iTable;           /* Table cursor number */
     int iColumn;          /* Table column number */
@@ -2252,7 +2250,6 @@
   char **azVar;        /* Pointers to names of parameters */
   Vdbe *pReprepare;    /* VM being reprepared (sqlite3Reprepare()) */
   int nAlias;          /* Number of aliased result set columns */
-  int nAliasAlloc;     /* Number of allocated slots for aAlias[] */
   int *aAlias;         /* Register used to hold aliased result */
   u8 explain;          /* True if the EXPLAIN flag is found on the query */
   Token sNameToken;    /* Token with unqualified schema object name */