diff --git a/const.go b/const.go
index 4a4dfeb..4a7bae3 100644
--- a/const.go
+++ b/const.go
@@ -73,6 +73,9 @@ const (
 	ERROR_MISSING_COLLSEQ   ExtendedErrorCode = xErrorCode(ERROR) | (1 << 8)
 	ERROR_RETRY             ExtendedErrorCode = xErrorCode(ERROR) | (2 << 8)
 	ERROR_SNAPSHOT          ExtendedErrorCode = xErrorCode(ERROR) | (3 << 8)
+	ERROR_RESERVESIZE       ExtendedErrorCode = xErrorCode(ERROR) | (4 << 8)
+	ERROR_KEY               ExtendedErrorCode = xErrorCode(ERROR) | (5 << 8)
+	ERROR_UNABLE            ExtendedErrorCode = xErrorCode(ERROR) | (6 << 8)
 	IOERR_READ              ExtendedErrorCode = xErrorCode(IOERR) | (1 << 8)
 	IOERR_SHORT_READ        ExtendedErrorCode = xErrorCode(IOERR) | (2 << 8)
 	IOERR_WRITE             ExtendedErrorCode = xErrorCode(IOERR) | (3 << 8)
@@ -107,6 +110,8 @@ const (
 	IOERR_DATA              ExtendedErrorCode = xErrorCode(IOERR) | (32 << 8)
 	IOERR_CORRUPTFS         ExtendedErrorCode = xErrorCode(IOERR) | (33 << 8)
 	IOERR_IN_PAGE           ExtendedErrorCode = xErrorCode(IOERR) | (34 << 8)
+	IOERR_BADKEY            ExtendedErrorCode = xErrorCode(IOERR) | (35 << 8)
+	IOERR_CODEC             ExtendedErrorCode = xErrorCode(IOERR) | (36 << 8)
 	LOCKED_SHAREDCACHE      ExtendedErrorCode = xErrorCode(LOCKED) | (1 << 8)
 	LOCKED_VTAB             ExtendedErrorCode = xErrorCode(LOCKED) | (2 << 8)
 	BUSY_RECOVERY           ExtendedErrorCode = xErrorCode(BUSY) | (1 << 8)
@@ -362,13 +367,14 @@ const (
 // CheckpointMode are all the checkpoint mode values.
 //
 // https://sqlite.org/c3ref/c_checkpoint_full.html
-type CheckpointMode uint32
+type CheckpointMode int32
 
 const (
-	CHECKPOINT_PASSIVE  CheckpointMode = 0 /* Do as much as possible w/o blocking */
-	CHECKPOINT_FULL     CheckpointMode = 1 /* Wait for writers, then checkpoint */
-	CHECKPOINT_RESTART  CheckpointMode = 2 /* Like FULL but wait for readers */
-	CHECKPOINT_TRUNCATE CheckpointMode = 3 /* Like RESTART but also truncate WAL */
+	CHECKPOINT_NOOP     CheckpointMode = -1 /* Do no work at all */
+	CHECKPOINT_PASSIVE  CheckpointMode = 0  /* Do as much as possible w/o blocking */
+	CHECKPOINT_FULL     CheckpointMode = 1  /* Wait for writers, then checkpoint */
+	CHECKPOINT_RESTART  CheckpointMode = 2  /* Like FULL but wait for readers */
+	CHECKPOINT_TRUNCATE CheckpointMode = 3  /* Like RESTART but also truncate WAL */
 )
 
 // TxnState are the allowed return values from [Conn.TxnState].
diff --git a/ext/array/array.go b/ext/array/array.go
index 3e111f0..938413e 100644
--- a/ext/array/array.go
+++ b/ext/array/array.go
@@ -59,7 +59,8 @@ func (c *cursor) Next() error {
 }
 
 func (c *cursor) RowID() (int64, error) {
-	return int64(c.rowID), nil
+	// One-based RowID for consistency with carray and other tables.
+	return int64(c.rowID) + 1, nil
 }
 
 func (c *cursor) Column(ctx sqlite3.Context, n int) error {
diff --git a/ext/closure/closure.go b/ext/closure/closure.go
index c882508..44b9679 100644
--- a/ext/closure/closure.go
+++ b/ext/closure/closure.go
@@ -154,6 +154,7 @@ func (c *closure) BestIndex(idx *sqlite3.IndexInfo) error {
 		return sqlite3.CONSTRAINT
 	}
 
+	idx.IdxFlags = sqlite3.INDEX_SCAN_HEX
 	idx.EstimatedCost = cost
 	idx.IdxNum = plan
 	return nil
diff --git a/internal/util/const.go b/internal/util/const.go
index 5e89018..031a702 100644
--- a/internal/util/const.go
+++ b/internal/util/const.go
@@ -39,6 +39,9 @@ const (
 	ERROR_MISSING_COLLSEQ   = ERROR | (1 << 8)
 	ERROR_RETRY             = ERROR | (2 << 8)
 	ERROR_SNAPSHOT          = ERROR | (3 << 8)
+	ERROR_RESERVESIZE       = ERROR | (4 << 8)
+	ERROR_KEY               = ERROR | (5 << 8)
+	ERROR_UNABLE            = ERROR | (6 << 8)
 	IOERR_READ              = IOERR | (1 << 8)
 	IOERR_SHORT_READ        = IOERR | (2 << 8)
 	IOERR_WRITE             = IOERR | (3 << 8)
@@ -73,6 +76,8 @@ const (
 	IOERR_DATA              = IOERR | (32 << 8)
 	IOERR_CORRUPTFS         = IOERR | (33 << 8)
 	IOERR_IN_PAGE           = IOERR | (34 << 8)
+	IOERR_BADKEY            = IOERR | (35 << 8)
+	IOERR_CODEC             = IOERR | (36 << 8)
 	LOCKED_SHAREDCACHE      = LOCKED | (1 << 8)
 	LOCKED_VTAB             = LOCKED | (2 << 8)
 	BUSY_RECOVERY           = BUSY | (1 << 8)
diff --git a/vtab.go b/vtab.go
index 0725eae..e1f3ad7 100644
--- a/vtab.go
+++ b/vtab.go
@@ -445,7 +445,8 @@ const (
 type IndexScanFlag uint32
 
 const (
-	INDEX_SCAN_UNIQUE IndexScanFlag = 1
+	INDEX_SCAN_UNIQUE IndexScanFlag = 0x00000001
+	INDEX_SCAN_HEX    IndexScanFlag = 0x00000002
 )
 
 func vtabModuleCallback(i vtabConstructor) func(_ context.Context, _ api.Module, _ ptr_t, _ int32, _, _, _ ptr_t) res_t {