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Overview
Comment:Fix a problem with resizing a hash table in sqlite3session.c.
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SHA1: 6e5907e14d3316d56313243c4f8ce8f14d0858fc
User & Date: dan 2011-03-19 16:26:12
Context
2011-03-19
17:07
Move session1.test from test/ to ext/session/. check-in: c4436a93 user: dan tags: sessions
16:26
Fix a problem with resizing a hash table in sqlite3session.c. check-in: 6e5907e1 user: dan tags: sessions
15:37
Fix some bugs in sqlite3changeset_apply(). check-in: 7250318d user: dan tags: sessions
Changes
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Changes to ext/session/session2.test.

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  CREATE TABLE t1(a PRIMARY KEY, b);
  CREATE TABLE t2(a, b INTEGER PRIMARY KEY);
  CREATE TABLE t3(a, b, c, PRIMARY KEY(a, b));
}

foreach {tn sql} {
  1 { INSERT INTO t1 VALUES(1, 2) } 

  2 {
    INSERT INTO t2 VALUES(1, NULL);
    INSERT INTO t2 VALUES(2, NULL);
    INSERT INTO t2 VALUES(3, NULL);
    DELETE FROM t2 WHERE a = 2;
    INSERT INTO t2 VALUES(4, NULL);
    UPDATE t2 SET b=0 WHERE b=1;
  } 

  3 { INSERT INTO t3 SELECT *, NULL FROM t2 }

  4 {
    INSERT INTO t3 SELECT a||a, b||b, NULL FROM t3;
    DELETE FROM t3 WHERE rowid%2;
  }

  5 { UPDATE t3 SET c = a||b }

  6 { UPDATE t1 SET a = 32 }
















} {
  do_then_apply_sql $sql
  do_test $tn { compare_db db db2 } {}
}

finish_test








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  CREATE TABLE t1(a PRIMARY KEY, b);
  CREATE TABLE t2(a, b INTEGER PRIMARY KEY);
  CREATE TABLE t3(a, b, c, PRIMARY KEY(a, b));
}

foreach {tn sql} {
  1 { INSERT INTO t1 VALUES(1, 2) } 

  2 {
    INSERT INTO t2 VALUES(1, NULL);
    INSERT INTO t2 VALUES(2, NULL);
    INSERT INTO t2 VALUES(3, NULL);
    DELETE FROM t2 WHERE a = 2;
    INSERT INTO t2 VALUES(4, NULL);
    UPDATE t2 SET b=0 WHERE b=1;
  } 

  3 { INSERT INTO t3 SELECT *, NULL FROM t2 }

  4 {
    INSERT INTO t3 SELECT a||a, b||b, NULL FROM t3;
    DELETE FROM t3 WHERE rowid%2;
  }

  5 { UPDATE t3 SET c = a||b }

  6 { UPDATE t1 SET a = 32 }

  7 { 
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --    2
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --    4
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --    8
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --   16
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --   32
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --   64
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --  128
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --  256
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; --  512
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; -- 1024
    INSERT INTO t1 SELECT randomblob(32), randomblob(32) FROM t1; -- 2048
    DELETE FROM t1 WHERE (rowid%3)==0;
  }

} {
  do_then_apply_sql $sql
  do_test $tn { compare_db db db2 } {}
}

finish_test

Changes to ext/session/sqlite3session.c.

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    }
  }

  *pnWrite += nByte;
  return SQLITE_OK;
}

#define HASH_APPEND(hash, add) ((hash) << 3) ^ (hash) ^ (int)(add)
static int sessionHashAppendI64(int h, i64 i){
  h = HASH_APPEND(h, i & 0xFFFFFFFF);
  return HASH_APPEND(h, (i>>32)&0xFFFFFFFF);
}
static int sessionHashAppendBlob(int h, int n, const u8 *z){
  int i;
  for(i=0; i<n; i++) h = HASH_APPEND(h, z[i]);
  return h;
}

/*

** This function calculates a hash based on the primary key values of
** the old.* or new.* row currently available.

*/
static int sessionPreupdateHash(
  sqlite3 *db,                    /* Database handle */
  SessionTable *pTab,             /* Session table handle */
  int bNew,                       /* True to hash the new.* PK */
  int *piHash                     /* OUT: Hash value */
){
  int h = 0;
  int i;

  assert( pTab->nCol==sqlite3_preupdate_count(db) );
  for(i=0; i<pTab->nCol; i++){
    if( pTab->abPK[i] ){
      int rc;
      int eType;
      sqlite3_value *pVal;
................................................................................
    }
  }

  *piHash = (h % pTab->nChange);
  return SQLITE_OK;
}







static int sessionChangeHash(
  sqlite3 *db,
  SessionTable *pTab,
  SessionChange *pChange,
  int nBucket

){
  int h = 0;
  int i;


  u8 *a = pChange->aRecord;

  for(i=0; i<pTab->nCol; i++){
    int eType = *a++;
    int isPK = pTab->abPK[i];

    if( isPK ) h = HASH_APPEND(h, eType);
    switch( eType ){







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    }
  }

  *pnWrite += nByte;
  return SQLITE_OK;
}

#define HASH_APPEND(hash, add) ((hash) << 3) ^ (hash) ^ (unsigned int)(add)
static unsigned int sessionHashAppendI64(unsigned int h, i64 i){
  h = HASH_APPEND(h, i & 0xFFFFFFFF);
  return HASH_APPEND(h, (i>>32)&0xFFFFFFFF);
}
static unsigned int sessionHashAppendBlob(unsigned int h, int n, const u8 *z){
  int i;
  for(i=0; i<n; i++) h = HASH_APPEND(h, z[i]);
  return h;
}

/*
** This function may only be called from within a pre-update callback.
** It calculates a hash based on the primary key values of the old.* or 
** new.* row currently available. The value returned is guaranteed to
** be less than pTab->nBucket.
*/
static unsigned int sessionPreupdateHash(
  sqlite3 *db,                    /* Database handle */
  SessionTable *pTab,             /* Session table handle */
  int bNew,                       /* True to hash the new.* PK */
  int *piHash                     /* OUT: Hash value */
){
  unsigned int h = 0;             /* Hash value to return */
  int i;                          /* Used to iterate through columns */

  assert( pTab->nCol==sqlite3_preupdate_count(db) );
  for(i=0; i<pTab->nCol; i++){
    if( pTab->abPK[i] ){
      int rc;
      int eType;
      sqlite3_value *pVal;
................................................................................
    }
  }

  *piHash = (h % pTab->nChange);
  return SQLITE_OK;
}

/*
** Based on the primary key values stored in change pChange, calculate a
** hash key, assuming the has table has nBucket buckets. The hash keys
** calculated by this function are compatible with those calculated by
** sessionPreupdateHash().
*/
static unsigned int sessionChangeHash(
  sqlite3 *db,                    /* Database handle */
  SessionTable *pTab,             /* Table handle */
  SessionChange *pChange,         /* Change handle */

  int nBucket                     /* Assume this many buckets in hash table */
){


  unsigned int h = 0;             /* Value to return */
  int i;                          /* Used to iterate through columns */
  u8 *a = pChange->aRecord;       /* Used to iterate through change record */

  for(i=0; i<pTab->nCol; i++){
    int eType = *a++;
    int isPK = pTab->abPK[i];

    if( isPK ) h = HASH_APPEND(h, eType);
    switch( eType ){