diff --git a/collects/db/TODO b/collects/db/TODO
index 8a91f306d1..3a69ba3572 100644
--- a/collects/db/TODO
+++ b/collects/db/TODO
@@ -1,4 +1,3 @@
-internal docs
 ----
 
 Testing
@@ -31,11 +30,11 @@ Types
 
 Misc
 
+- internal docs
+
 - use ffi/unsafe/alloc to simplify odbc handle allocation
 
 - add ODBC-like functions for inspecting schemas (list-tables, etc)
-  - util/schema (?), util/info (for information_schema) (?)
-  - at least, table-exists? : string [...] -> boolean?
 
 - for wrapped/managed connections, detect if underlying connection gets
   disconnected by server (eg, times out after 10 minutes of inactivity)
diff --git a/collects/db/base.rkt b/collects/db/base.rkt
index 158b0a7093..7fc39c6d71 100644
--- a/collects/db/base.rkt
+++ b/collects/db/base.rkt
@@ -1,9 +1,248 @@
 #lang racket/base
 (require racket/contract
-         "private/generic/main.rkt"
-         "private/generic/connect-util.rkt"
-         "private/generic/dsn.rkt")
+         unstable/prop-contract)
 
-(provide (all-from-out "private/generic/main.rkt")
-         (all-from-out "private/generic/dsn.rkt")
-         (all-from-out "private/generic/connect-util.rkt"))
+;; ============================================================
+
+(require "private/generic/interfaces.rkt"
+         "private/generic/sql-data.rkt")
+
+(provide (struct-out simple-result)
+         (struct-out rows-result)
+         statement-binding?)
+
+(provide sql-null
+         sql-null?
+         sql-null->false
+         false->sql-null)
+
+(provide/contract
+ [struct sql-date ([year exact-integer?]
+                   [month (integer-in 0 12)]
+                   [day (integer-in 0 31)])]
+ [struct sql-time ([hour (integer-in 0 23)]
+                   [minute (integer-in 0 59)]
+                   [second (integer-in 0 61)] ;; leap seconds
+                   [nanosecond (integer-in 0 (sub1 #e1e9))]
+                   [tz (or/c #f exact-integer?)])]
+ [struct sql-timestamp ([year exact-integer?]
+                        [month (integer-in 0 12)]
+                        [day (integer-in 0 31)]
+                        [hour (integer-in 0 23)]
+                        [minute (integer-in 0 59)]
+                        [second (integer-in 0 61)]
+                        [nanosecond (integer-in 0 (sub1 #e1e9))]
+                        [tz (or/c #f exact-integer?)])]
+ [struct sql-interval ([years exact-integer?]
+                       [months exact-integer?]
+                       [days exact-integer?]
+                       [hours exact-integer?]
+                       [minutes exact-integer?]
+                       [seconds exact-integer?]
+                       [nanoseconds exact-integer?])]
+
+ [sql-day-time-interval?
+  (-> any/c boolean?)]
+ [sql-year-month-interval?
+  (-> any/c boolean?)]
+ [sql-interval->sql-time
+  (->* (sql-interval?) (any/c)
+       any)]
+ [sql-time->sql-interval
+  (-> sql-time? sql-day-time-interval?)]
+
+ [make-sql-bits
+  (-> exact-nonnegative-integer? sql-bits?)]
+ [sql-bits?
+  (-> any/c boolean?)]
+ [sql-bits-length
+  (-> sql-bits? exact-nonnegative-integer?)]
+ [sql-bits-ref
+  (-> sql-bits? exact-nonnegative-integer? boolean?)]
+ [sql-bits-set!
+  (-> sql-bits? exact-nonnegative-integer? boolean? void?)]
+ [sql-bits->list
+  (-> sql-bits? (listof boolean?))]
+ [list->sql-bits
+  (-> (listof boolean?) sql-bits?)]
+ [sql-bits->string
+  (-> sql-bits? string?)]
+ [string->sql-bits
+  (-> string? sql-bits?)])
+
+;; ============================================================
+
+(require "private/generic/functions.rkt")
+
+(provide (rename-out [in-query* in-query]))
+
+(provide/contract
+ [connection?
+  (-> any/c any)]
+ [disconnect
+  (-> connection? any)]
+ [connected?
+  (-> connection? any)]
+ [connection-dbsystem
+  (-> connection? dbsystem?)]
+ [dbsystem?
+  (-> any/c any)]
+ [dbsystem-name
+  (-> dbsystem? symbol?)]
+ [dbsystem-supported-types
+  (-> dbsystem? (listof symbol?))]
+
+ [statement?
+  (-> any/c any)]
+ [prepared-statement?
+  (-> any/c any)]
+ [prepared-statement-parameter-types
+  (-> prepared-statement? (or/c list? #f))]
+ [prepared-statement-result-types
+  (-> prepared-statement? (or/c list? #f))]
+
+ [query-exec
+  (->* (connection? statement?) () #:rest list? any)]
+ [query-rows
+  (->* (connection? statement?) () #:rest list? (listof vector?))]
+ [query-list
+  (->* (connection? statement?) () #:rest list? list?)]
+ [query-row
+  (->* (connection? statement?) () #:rest list? vector?)]
+ [query-maybe-row
+  (->* (connection? statement?) () #:rest list? (or/c #f vector?))]
+ [query-value
+  (->* (connection? statement?) () #:rest list? any)]
+ [query-maybe-value
+  (->* (connection? statement?) () #:rest list? any)]
+ [query
+  (->* (connection? statement?) () #:rest list? any)]
+
+ [prepare
+  (-> connection? (or/c string? virtual-statement?) any)]
+ [bind-prepared-statement
+  (-> prepared-statement? list? any)]
+
+ [rename virtual-statement* virtual-statement
+  (-> (or/c string? (-> dbsystem? string?))
+      virtual-statement?)]
+ [virtual-statement?
+  (-> any/c boolean?)]
+
+ [start-transaction
+  (->* (connection?)
+       (#:isolation (or/c 'serializable 'repeatable-read 'read-committed 'read-uncommitted #f))
+       void?)]
+ [commit-transaction
+  (-> connection? void?)]
+ [rollback-transaction
+  (-> connection? void?)]
+ [in-transaction?
+  (-> connection? boolean?)]
+ [needs-rollback?
+  (-> connection? boolean?)]
+ [call-with-transaction
+  (->* (connection? (-> any))
+       (#:isolation (or/c 'serializable 'repeatable-read 'read-committed 'read-uncommitted #f))
+       void?)]
+
+ [prop:statement
+  (struct-type-property/c
+   (-> any/c connection?
+       statement?))]
+
+ [list-tables
+  (->* (connection?)
+       (#:schema (or/c 'search-or-current 'search 'current))
+       (listof string?))]
+ [table-exists?
+  (->* (connection? string?)
+       (#:schema (or/c 'search-or-current 'search 'current)
+        #:case-sensitive? any/c)
+       boolean?)]
+
+ [group-rows
+  (->* (rows-result?
+        #:group (or/c (vectorof string?) (listof (vectorof string?))))
+       (#:group-mode (listof (or/c 'preserve-null-rows 'list)))
+       rows-result?)])
+
+;; ============================================================
+
+(require "private/generic/connect-util.rkt")
+
+(provide/contract
+ [kill-safe-connection
+  (-> connection? connection?)]
+ [virtual-connection
+  (->* ((or/c (-> connection?) connection-pool?))
+       ()
+       connection?)]
+ [connection-pool
+  (->* ((-> connection?))
+       (#:max-connections (or/c (integer-in 1 10000) +inf.0)
+        #:max-idle-connections (or/c (integer-in 1 10000) +inf.0))
+       connection-pool?)]
+ [connection-pool?
+  (-> any/c boolean?)]
+ [connection-pool-lease
+  (->* (connection-pool?)
+       ((or/c custodian? evt?))
+       connection?)])
+
+;; ============================================================
+
+(require "private/generic/dsn.rkt")
+
+(provide dsn-connect)   ;; can't express "or any kw at all" w/ ->* contract
+(provide/contract
+ [struct data-source
+         ([connector connector?]
+          [args arglist?]
+          [extensions (listof (list/c symbol? writable-datum?))])]
+ [current-dsn-file (parameter/c path-string?)]
+ [get-dsn
+  (->* (symbol?) (any/c #:dsn-file path-string?) any)]
+ [put-dsn
+  (->* (symbol? (or/c data-source? #f)) (#:dsn-file path-string?) void?)]
+ [postgresql-data-source
+  (->* ()
+       (#:user string?
+        #:database string?
+        #:server string?
+        #:port exact-positive-integer?
+        #:socket (or/c string? 'guess)
+        #:password (or/c string? #f)
+        #:allow-cleartext-password? boolean?
+        #:ssl (or/c 'yes 'optional 'no)
+        #:notice-handler (or/c 'output 'error)
+        #:notification-handler (or/c 'output 'error))
+       data-source?)]
+ [mysql-data-source
+  (->* ()
+       (#:user string?
+        #:database string?
+        #:server string?
+        #:port exact-positive-integer?
+        #:socket (or/c string? 'guess)
+        #:password (or/c string? #f)
+        #:notice-handler (or/c 'output 'error))
+       data-source?)]
+ [sqlite3-data-source
+  (->* ()
+       (#:database (or/c string? 'memory 'temporary)
+        #:mode (or/c 'read-only 'read/write 'create)
+        #:busy-retry-limit (or/c exact-nonnegative-integer? +inf.0)
+        #:busy-retry-delay (and/c rational? (not/c negative?))
+        #:use-place boolean?)
+       data-source?)]
+ [odbc-data-source
+  (->* ()
+       (#:dsn string?
+        #:user string?
+        #:password string?
+        #:notice-handler (or/c 'output 'error)
+        #:strict-parameter-types? boolean?
+        #:character-mode (or/c 'wchar 'utf-8 'latin-1)
+        #:use-place boolean?)
+       data-source?)])
diff --git a/collects/db/main.rkt b/collects/db/main.rkt
index 5d759ecc66..673c48b3e5 100644
--- a/collects/db/main.rkt
+++ b/collects/db/main.rkt
@@ -2,7 +2,6 @@
 (require (for-syntax racket/base)
          "private/generic/lazy-require.rkt"
          racket/runtime-path
-         racket/promise
          racket/contract
          "base.rkt")
 (provide (all-from-out "base.rkt"))
@@ -49,7 +48,7 @@
         #:ssl-context ssl-client-context?
         #:notice-handler (or/c 'output 'error output-port? procedure?)
         #:notification-handler (or/c 'output 'error output-port? procedure?))
-       any/c)]
+       connection?)]
  [postgresql-guess-socket-path
   (-> path-string?)]
  [postgresql-password-hash
@@ -64,7 +63,7 @@
         #:port (or/c exact-positive-integer? #f)
         #:socket (or/c path-string? 'guess #f)
         #:notice-handler (or/c 'output 'error output-port? procedure?))
-       any/c)]
+       connection?)]
  [mysql-guess-socket-path
   (-> path-string?)]
  [mysql-password-hash
@@ -77,7 +76,7 @@
         #:busy-retry-limit (or/c exact-nonnegative-integer? +inf.0)
         #:busy-retry-delay (and/c rational? (not/c negative?))
         #:use-place boolean?)
-       any/c)]
+       connection?)]
 
  ;; Duplicates contracts at odbc.rkt
  [odbc-connect
diff --git a/collects/db/mysql.rkt b/collects/db/mysql.rkt
index 001cdfaade..ba78e4ce2c 100644
--- a/collects/db/mysql.rkt
+++ b/collects/db/mysql.rkt
@@ -13,7 +13,7 @@
         #:port (or/c exact-positive-integer? #f)
         #:socket (or/c path-string? 'guess #f)
         #:notice-handler (or/c 'output 'error output-port? procedure?))
-       any/c)]
+       connection?)]
  [mysql-guess-socket-path
   (-> path-string?)]
  [mysql-password-hash
diff --git a/collects/db/postgresql.rkt b/collects/db/postgresql.rkt
index 2830bce7c2..e36267e82f 100644
--- a/collects/db/postgresql.rkt
+++ b/collects/db/postgresql.rkt
@@ -18,7 +18,7 @@
         #:ssl-context ssl-client-context?
         #:notice-handler (or/c 'output 'error output-port? procedure?)
         #:notification-handler (or/c 'output 'error output-port? procedure?))
-       any/c)]
+       connection?)]
  [postgresql-guess-socket-path
   (-> path-string?)]
  [postgresql-password-hash
diff --git a/collects/db/private/generic/connect-util.rkt b/collects/db/private/generic/connect-util.rkt
index 8cf6af3f12..87d23a0523 100644
--- a/collects/db/private/generic/connect-util.rkt
+++ b/collects/db/private/generic/connect-util.rkt
@@ -1,8 +1,11 @@
 #lang racket/base
-(require racket/contract
-         racket/class
-         "interfaces.rkt"
-         (only-in "functions.rkt" connection?))
+(require racket/class
+         "interfaces.rkt")
+(provide kill-safe-connection
+         virtual-connection
+         connection-pool
+         connection-pool?
+         connection-pool-lease)
 
 ;; manager% implements kill-safe manager thread w/ request channel
 (define manager%
@@ -376,24 +379,3 @@
       (uerror 'connection-pool-lease
               "cannot obtain connection; connection pool limit reached"))
     result))
-
-;; ========================================
-
-(provide/contract
- [kill-safe-connection
-  (-> connection? connection?)]
- [virtual-connection
-  (->* ((or/c (-> connection?) connection-pool?))
-       ()
-       connection?)]
- [connection-pool
-  (->* ((-> connection?))
-       (#:max-connections (or/c (integer-in 1 10000) +inf.0)
-        #:max-idle-connections (or/c (integer-in 1 10000) +inf.0))
-       connection-pool?)]
- [connection-pool?
-  (-> any/c boolean?)]
- [connection-pool-lease
-  (->* (connection-pool?)
-       ((or/c custodian? evt?))
-       connection?)])
diff --git a/collects/db/private/generic/dsn.rkt b/collects/db/private/generic/dsn.rkt
index 5455726a0d..177b659cc1 100644
--- a/collects/db/private/generic/dsn.rkt
+++ b/collects/db/private/generic/dsn.rkt
@@ -1,12 +1,21 @@
 #lang racket/base
 (require "lazy-require.rkt"
-         racket/contract
          racket/match
          racket/file
          racket/list
-         racket/runtime-path
-         racket/promise
-         "main.rkt")
+         racket/runtime-path)
+(provide dsn-connect
+         (struct-out data-source)
+         connector?
+         arglist?
+         writable-datum?
+         current-dsn-file
+         get-dsn
+         put-dsn
+         postgresql-data-source
+         mysql-data-source
+         sqlite3-data-source
+         odbc-data-source)
 
 (define-lazy-require-definer define-main "../../main.rkt")
 
@@ -47,15 +56,15 @@ considered important.
 
 (define none (gensym 'none))
 
-(define (datum? x)
+(define (writable-datum? x)
   (or (symbol? x)
       (string? x)
       (number? x)
       (boolean? x)
       (null? x)
       (and (pair? x)
-           (datum? (car x))
-           (datum? (cdr x)))))
+           (writable-datum? (car x))
+           (writable-datum? (cdr x)))))
 
 (define (connector? x)
   (memq x '(postgresql mysql sqlite3 odbc)))
@@ -72,11 +81,11 @@ considered important.
                      (reverse kwargs))]
               [(keyword? (car x))
                (cond [(null? (cdr x)) (fail "keyword without argument: ~a" (car x))]
-                     [(datum? (cadr x))
+                     [(writable-datum? (cadr x))
                       (loop (cddr x) pargs (cons (list (car x) (cadr x)) kwargs))]
                      [else
                       (fail "expected readable datum: ~e" (cadr x))])]
-              [(datum? (car x))
+              [(writable-datum? (car x))
                (loop (cdr x) (cons (car x) pargs) kwargs)]
               [else (fail "expected readable datum: ~e" (car x))]))
       (fail "expected list")))
@@ -93,7 +102,7 @@ considered important.
     (if (list? x)
         (map (lambda (x)
                (match x
-                 [(list (? symbol? key) (? datum? value))
+                 [(list (? symbol? key) (? writable-datum? value))
                   x]
                  [else (fail "expected extension entry: ~e" x)]))
              x)
@@ -195,56 +204,3 @@ considered important.
   (mk-specialized 'odbc-data-source 'odbc 0
                   '(#:dsn #:user #:password #:notice-handler
                     #:strict-parameter-types? #:character-mode #:use-place)))
-
-(provide/contract
- [struct data-source
-         ([connector connector?]
-          [args arglist?]
-          [extensions (listof (list/c symbol? datum?))])]
- [dsn-connect procedure?] ;; Can't express "or any kw at all" w/ ->* contract.
- [current-dsn-file (parameter/c path-string?)]
- [get-dsn
-  (->* (symbol?) (any/c #:dsn-file path-string?) any)]
- [put-dsn
-  (->* (symbol? (or/c data-source? #f)) (#:dsn-file path-string?) void?)]
- [postgresql-data-source
-  (->* ()
-       (#:user string?
-        #:database string?
-        #:server string?
-        #:port exact-positive-integer?
-        #:socket (or/c string? 'guess)
-        #:password (or/c string? #f)
-        #:allow-cleartext-password? boolean?
-        #:ssl (or/c 'yes 'optional 'no)
-        #:notice-handler (or/c 'output 'error)
-        #:notification-handler (or/c 'output 'error))
-       data-source?)]
- [mysql-data-source
-  (->* ()
-       (#:user string?
-        #:database string?
-        #:server string?
-        #:port exact-positive-integer?
-        #:socket (or/c string? 'guess)
-        #:password (or/c string? #f)
-        #:notice-handler (or/c 'output 'error))
-       data-source?)]
- [sqlite3-data-source
-  (->* ()
-       (#:database (or/c string? 'memory 'temporary)
-        #:mode (or/c 'read-only 'read/write 'create)
-        #:busy-retry-limit (or/c exact-nonnegative-integer? +inf.0)
-        #:busy-retry-delay (and/c rational? (not/c negative?))
-        #:use-place boolean?)
-       data-source?)]
- [odbc-data-source
-  (->* ()
-       (#:dsn string?
-        #:user string?
-        #:password string?
-        #:notice-handler (or/c 'output 'error)
-        #:strict-parameter-types? boolean?
-        #:character-mode (or/c 'wchar 'utf-8 'latin-1)
-        #:use-place boolean?)
-       data-source?)])
diff --git a/collects/db/private/generic/functions.rkt b/collects/db/private/generic/functions.rkt
index d5bd0e8f20..554fb73fb9 100644
--- a/collects/db/private/generic/functions.rkt
+++ b/collects/db/private/generic/functions.rkt
@@ -1,11 +1,10 @@
 #lang racket/base
 (require (for-syntax racket/base)
-         racket/contract
          racket/vector
-         unstable/prop-contract
          racket/class
          "interfaces.rkt"
          (only-in "sql-data.rkt" sql-null sql-null?))
+(provide (all-defined-out))
 
 ;; == Administrative procedures
 
@@ -42,9 +41,6 @@
       (statement-binding? x)
       (prop:statement? x)))
 
-(define complete-statement?
-  (or/c string? statement-binding?))
-
 (define (bind-prepared-statement pst params)
   (send pst bind 'bind-prepared-statement params))
 
@@ -304,110 +300,6 @@
 ;; list-tables* : ... -> (listof vector)
 ;; Return full catalog/schema/table/type list.
 
-;; ========================================
-
-(define preparable/c (or/c string? virtual-statement?))
-
-(provide (rename-out [in-query* in-query]))
-
-(provide/contract
- [connection?
-  (-> any/c any)]
- [disconnect
-  (-> connection? any)]
- [connected?
-  (-> connection? any)]
- [connection-dbsystem
-  (-> connection? dbsystem?)]
- [dbsystem?
-  (-> any/c any)]
- [dbsystem-name
-  (-> dbsystem? symbol?)]
- [dbsystem-supported-types
-  (-> dbsystem? (listof symbol?))]
-
- [statement?
-  (-> any/c any)]
- [prepared-statement?
-  (-> any/c any)]
- [prepared-statement-parameter-types
-  (-> prepared-statement? (or/c list? #f))]
- [prepared-statement-result-types
-  (-> prepared-statement? (or/c list? #f))]
-
- [query-exec
-  (->* (connection? statement?) () #:rest list? any)]
- [query-rows
-  (->* (connection? statement?) () #:rest list? (listof vector?))]
- [query-list
-  (->* (connection? statement?) () #:rest list? list?)]
- [query-row
-  (->* (connection? statement?) () #:rest list? vector?)]
- [query-maybe-row
-  (->* (connection? statement?) () #:rest list? (or/c #f vector?))]
- [query-value
-  (->* (connection? statement?) () #:rest list? any)]
- [query-maybe-value
-  (->* (connection? statement?) () #:rest list? any)]
- [query
-  (->* (connection? statement?) () #:rest list? any)]
-
- #|
- [in-query
-  (->* (connection? statement?) () #:rest list? sequence?)]
- |#
-
- [prepare
-  (-> connection? preparable/c any)]
- [bind-prepared-statement
-  (-> prepared-statement? list? any)]
-
- [rename virtual-statement* virtual-statement
-  (-> (or/c string? (-> dbsystem? string?))
-      virtual-statement?)]
- [virtual-statement?
-  (-> any/c boolean?)]
-
- [start-transaction
-  (->* (connection?)
-       (#:isolation (or/c 'serializable 'repeatable-read 'read-committed 'read-uncommitted #f))
-       void?)]
- [commit-transaction
-  (-> connection? void?)]
- [rollback-transaction
-  (-> connection? void?)]
- [in-transaction?
-  (-> connection? boolean?)]
- [needs-rollback?
-  (-> connection? boolean?)]
- [call-with-transaction
-  (->* (connection? (-> any))
-       (#:isolation (or/c 'serializable 'repeatable-read 'read-committed 'read-uncommitted #f))
-       void?)]
-
- [prop:statement
-  (struct-type-property/c
-   (-> any/c connection?
-       statement?))]
-
- [list-tables
-  (->* (connection?)
-       (#:schema (or/c 'search-or-current 'search 'current))
-       (listof string?))]
- [table-exists?
-  (->* (connection? string?)
-       (#:schema (or/c 'search-or-current 'search 'current)
-        #:case-sensitive? any/c)
-       boolean?)]
-
-#|
- [get-schemas
-  (-> connection? (listof vector?))]
- [get-tables
-  (-> connection? (listof vector?))]
-|#)
-
-
 ;; ========================================
 
 (define (group-rows result
@@ -553,10 +445,3 @@
                                    invert-outer?
                                    as-list?)])
                  (vector-append key (vector residuals))))))]))
-
-(provide/contract
- [group-rows
-  (->* (rows-result?
-        #:group (or/c (vectorof string?) (listof (vectorof string?))))
-       (#:group-mode (listof (or/c 'preserve-null-rows 'list)))
-       rows-result?)])
diff --git a/collects/db/private/generic/main.rkt b/collects/db/private/generic/main.rkt
deleted file mode 100644
index 505209c3c1..0000000000
--- a/collects/db/private/generic/main.rkt
+++ /dev/null
@@ -1,68 +0,0 @@
-#lang racket/base
-(require racket/contract
-         "interfaces.rkt"
-         "sql-data.rkt"
-         "functions.rkt")
-(provide (struct-out simple-result)
-         (struct-out rows-result)
-         statement-binding?
-         (all-from-out "functions.rkt"))
-
-(provide sql-null
-         sql-null?
-         sql-null->false
-         false->sql-null)
-
-(provide/contract
- [struct sql-date ([year exact-integer?]
-                   [month (integer-in 0 12)]
-                   [day (integer-in 0 31)])]
- [struct sql-time ([hour (integer-in 0 23)]
-                   [minute (integer-in 0 59)]
-                   [second (integer-in 0 61)] ;; leap seconds
-                   [nanosecond (integer-in 0 (sub1 #e1e9))]
-                   [tz (or/c #f exact-integer?)])]
- [struct sql-timestamp ([year exact-integer?]
-                        [month (integer-in 0 12)]
-                        [day (integer-in 0 31)]
-                        [hour (integer-in 0 23)]
-                        [minute (integer-in 0 59)]
-                        [second (integer-in 0 61)]
-                        [nanosecond (integer-in 0 (sub1 #e1e9))]
-                        [tz (or/c #f exact-integer?)])]
- [struct sql-interval ([years exact-integer?]
-                       [months exact-integer?]
-                       [days exact-integer?]
-                       [hours exact-integer?]
-                       [minutes exact-integer?]
-                       [seconds exact-integer?]
-                       [nanoseconds exact-integer?])]
-
- [sql-day-time-interval?
-  (-> any/c boolean?)]
- [sql-year-month-interval?
-  (-> any/c boolean?)]
- [sql-interval->sql-time
-  (->* (sql-interval?) (any/c)
-       any)]
- [sql-time->sql-interval
-  (-> sql-time? sql-day-time-interval?)]
-
- [make-sql-bits
-  (-> exact-nonnegative-integer? sql-bits?)]
- [sql-bits?
-  (-> any/c boolean?)]
- [sql-bits-length
-  (-> sql-bits? exact-nonnegative-integer?)]
- [sql-bits-ref
-  (-> sql-bits? exact-nonnegative-integer? boolean?)]
- [sql-bits-set!
-  (-> sql-bits? exact-nonnegative-integer? boolean? void?)]
- [sql-bits->list
-  (-> sql-bits? (listof boolean?))]
- [list->sql-bits
-  (-> (listof boolean?) sql-bits?)]
- [sql-bits->string
-  (-> sql-bits? string?)]
- [string->sql-bits
-  (-> string? sql-bits?)])
diff --git a/collects/db/private/generic/sql-convert.rkt b/collects/db/private/generic/sql-convert.rkt
index ac6eac4dc8..897a7e1742 100644
--- a/collects/db/private/generic/sql-convert.rkt
+++ b/collects/db/private/generic/sql-convert.rkt
@@ -1,5 +1,4 @@
 #lang racket/base
-(require "sql-data.rkt")
 
 ;; ========================================
 
diff --git a/collects/db/private/mysql/main.rkt b/collects/db/private/mysql/main.rkt
index 80d142e2be..e03057c8c3 100644
--- a/collects/db/private/mysql/main.rkt
+++ b/collects/db/private/mysql/main.rkt
@@ -1,16 +1,13 @@
 #lang racket/base
-(require racket/contract
-         racket/class
+(require racket/class
          racket/tcp
          file/sha1
          "../generic/interfaces.rkt"
          "../generic/socket.rkt"
-         "connection.rkt"
-         "dbsystem.rkt")
+         "connection.rkt")
 (provide mysql-connect
          mysql-guess-socket-path
-         mysql-password-hash
-         (rename-out [dbsystem mysql-dbsystem]))
+         mysql-password-hash)
 
 (define (mysql-connect #:user user
                        #:database database
diff --git a/collects/db/private/odbc/dbsystem.rkt b/collects/db/private/odbc/dbsystem.rkt
index f6ade4e336..bbef44b51d 100644
--- a/collects/db/private/odbc/dbsystem.rkt
+++ b/collects/db/private/odbc/dbsystem.rkt
@@ -1,11 +1,8 @@
 #lang racket/base
 (require racket/class
-         ffi/unsafe
-         ffi/unsafe/atomic
          "../generic/interfaces.rkt"
          "../generic/sql-data.rkt"
-         "../generic/sql-convert.rkt"
-         "ffi.rkt")
+         "../generic/sql-convert.rkt")
 (provide dbsystem
          supported-typeid?)
 
diff --git a/collects/db/private/odbc/ffi.rkt b/collects/db/private/odbc/ffi.rkt
index 404cd0db38..370190b06d 100644
--- a/collects/db/private/odbc/ffi.rkt
+++ b/collects/db/private/odbc/ffi.rkt
@@ -1,6 +1,5 @@
 #lang racket/base
-(require (rename-in racket/contract [-> c->])
-         ffi/unsafe
+(require ffi/unsafe
          ffi/unsafe/define
          "ffi-constants.rkt")
 (provide (all-from-out "ffi-constants.rkt"))
diff --git a/collects/db/private/odbc/main.rkt b/collects/db/private/odbc/main.rkt
index f138a4ae05..b5a63c6f70 100644
--- a/collects/db/private/odbc/main.rkt
+++ b/collects/db/private/odbc/main.rkt
@@ -1,6 +1,5 @@
 #lang racket/base
 (require racket/class
-         racket/contract
          "../generic/interfaces.rkt"
          "../generic/place-client.rkt"
          "connection.rkt"
diff --git a/collects/db/private/postgresql/main.rkt b/collects/db/private/postgresql/main.rkt
index 698ca42f7e..9f3311bc80 100644
--- a/collects/db/private/postgresql/main.rkt
+++ b/collects/db/private/postgresql/main.rkt
@@ -1,16 +1,13 @@
 #lang racket/base
 (require racket/class
-         racket/contract
          racket/tcp
          openssl
          "../generic/interfaces.rkt"
          "../generic/socket.rkt"
-         "connection.rkt"
-         "dbsystem.rkt")
+         "connection.rkt")
 (provide postgresql-connect
          postgresql-guess-socket-path
-         postgresql-password-hash
-         (rename-out [dbsystem postgresql-dbsystem]))
+         postgresql-password-hash)
 
 (define (postgresql-connect #:user user
                             #:database database
diff --git a/collects/db/private/sqlite3/dbsystem.rkt b/collects/db/private/sqlite3/dbsystem.rkt
index 12d1e2d1d6..86de61b153 100644
--- a/collects/db/private/sqlite3/dbsystem.rkt
+++ b/collects/db/private/sqlite3/dbsystem.rkt
@@ -1,8 +1,6 @@
 #lang racket/base
 (require racket/class
-         "../generic/interfaces.rkt"
-         "../generic/sql-data.rkt"
-         "ffi-constants.rkt")
+         "../generic/interfaces.rkt")
 (provide dbsystem)
 
 (define sqlite3-dbsystem%
diff --git a/collects/db/scribblings/config.rkt b/collects/db/scribblings/config.rkt
index 2b79af2683..c3be75a1ed 100644
--- a/collects/db/scribblings/config.rkt
+++ b/collects/db/scribblings/config.rkt
@@ -1,7 +1,6 @@
 #lang racket/base
 (require scribble/manual
          scribble/eval
-         racket/sandbox
          (for-label racket/base
                     racket/contract))
 (provide (all-defined-out)
diff --git a/collects/db/sqlite3.rkt b/collects/db/sqlite3.rkt
index f0d1c9b492..26f17efc10 100644
--- a/collects/db/sqlite3.rkt
+++ b/collects/db/sqlite3.rkt
@@ -11,4 +11,4 @@
         #:busy-retry-limit (or/c exact-nonnegative-integer? +inf.0)
         #:busy-retry-delay (and/c rational? (not/c negative?))
         #:use-place any/c)
-       any/c)])
+       connection?)])
diff --git a/collects/db/util/private/geometry.rkt b/collects/db/util/private/geometry.rkt
index c674fbb3aa..07617a7961 100644
--- a/collects/db/util/private/geometry.rkt
+++ b/collects/db/util/private/geometry.rkt
@@ -1,6 +1,5 @@
 #lang racket/base
-(require racket/contract
-         racket/list)
+(require racket/list)
 (provide (all-defined-out))
 
 #|