Implement MySQL migration option "downcase|quote identifier".

mysql-cast-rules.lisp

@@ -7,6 +7,12 @@
 ;;;
 ;;; Some functions to deal with ENUM types
 ;;;
+(defun apply-identifier-case (identifier case)
+  "Return a SQL string to use in the output part of a MySQL query."
+  (ecase case
+    (:downcase (string-downcase identifier))
+    (:quote    (format nil "\"~a\"" identifier))))
+
 (defun explode-mysql-enum (ctype)
   "Convert MySQL ENUM expression into a list of labels."
   ;; from: "ENUM('small', 'medium', 'large')"
@@ -14,15 +20,17 @@
   (mapcar (lambda (x) (string-trim "' )" x))
 	  (sq:split-sequence #\, ctype  :start (position #\' ctype))))
 
-(defun get-enum-type-name (table-name column-name)
+(defun get-enum-type-name (table-name column-name identifier-case)
   "Return the Type Name we're going to use in PostgreSQL."
-  (format nil "~a_~a" table-name column-name))
+  (apply-identifier-case (format nil "~a_~a" table-name column-name)
+			 identifier-case))
 
-(defun get-create-enum (table-name column-name ctype)
+(defun get-create-enum (table-name column-name ctype
+			&key (identifier-case :downcase))
   "Return a PostgreSQL CREATE ENUM TYPE statement from MySQL enum column."
   (with-output-to-string (s)
     (format s "CREATE TYPE ~a AS ENUM (~{'~a'~^, ~});"
-	    (get-enum-type-name table-name column-name)
+	    (get-enum-type-name table-name column-name identifier-case)
 	    (explode-mysql-enum ctype))))
 
 (defun cast-enum (table-name column-name type ctype typemod)

mysql.lisp

@@ -72,45 +72,65 @@ order by table_name, ordinal_position" dbname)))
     ;; free resources
     (cl-mysql:disconnect)))
 
-(defun get-create-type (table-name cols &key include-drop)
+(defun get-create-type (table-name cols &key identifier-case include-drop)
   "MySQL declares ENUM types inline, PostgreSQL wants explicit CREATE TYPE."
   (loop
      for (name dtype ctype default nullable extra) in cols
      when (string-equal "enum" dtype)
      collect (when include-drop
-	       (let ((type-name (get-enum-type-name table-name name)))
+	       (let* ((type-name
+		       (get-enum-type-name table-name name identifier-case)))
 		 (format nil "DROP TYPE IF EXISTS ~a;" type-name)))
-     and collect (get-create-enum table-name name ctype)))
+     and collect (get-create-enum table-name name ctype
+				  :identifier-case identifier-case)))
 
-(defun get-create-table (table-name cols)
+(defun get-create-table (table-name cols &key identifier-case)
   "Return a PostgreSQL CREATE TABLE statement from MySQL columns"
   (with-output-to-string (s)
-    (format s "CREATE TABLE ~a ~%(~%" table-name)
+    (let ((table-name (apply-identifier-case table-name identifier-case)))
+      (format s "CREATE TABLE ~a ~%(~%" table-name))
     (loop
        for ((name dtype ctype default nullable extra) . last?) on cols
        for pg-coldef = (cast table-name name dtype ctype default nullable extra)
-       do (format s "  \"~a\" ~22t ~a~:[~;,~]~%" name pg-coldef last?))
+       for colname = (apply-identifier-case name identifier-case)
+       do (format s "  ~a ~22t ~a~:[~;,~]~%" colname pg-coldef last?))
     (format s ");~%")))
 
-(defun get-drop-table-if-exists (table-name)
+(defun get-drop-table-if-exists (table-name &key identifier-case)
   "Return the PostgreSQL DROP TABLE IF EXISTS statement for TABLE-NAME."
-  (format nil "DROP TABLE IF EXISTS ~a;~%" table-name))
+  (let ((table-name (apply-identifier-case table-name identifier-case)))
+    (format nil "DROP TABLE IF EXISTS ~a;~%" table-name)))
 
-(defun get-pgsql-create-tables (all-columns &key include-drop)
+(defun get-pgsql-create-tables (all-columns
+				&key
+				  include-drop
+				  (identifier-case :downcase))
   "Return the list of CREATE TABLE statements to run against PostgreSQL"
   (loop
      for (table-name . cols) in all-columns
-     for extra-types = (get-create-type table-name cols :include-drop include-drop)
+     for extra-types = (get-create-type table-name cols
-     when include-drop collect (get-drop-table-if-exists table-name)
+					:identifier-case identifier-case
+					:include-drop include-drop)
+     when include-drop
+     collect (get-drop-table-if-exists table-name
+				       :identifier-case identifier-case)
+
      when extra-types append extra-types
-     collect (get-create-table table-name cols)))
+
+     collect (get-create-table table-name cols
+			       :identifier-case identifier-case)))
 
 (defun pgsql-create-tables (dbname all-columns
-			    &key (pg-dbname dbname) include-drop)
+			    &key
+			      (identifier-case :downcase)
+			      (pg-dbname dbname)
+			      include-drop)
   "Create all MySQL tables in database dbname in PostgreSQL"
   (loop
      for nb-tables from 0
-     for sql in (get-pgsql-create-tables all-columns :include-drop include-drop)
+     for sql in (get-pgsql-create-tables all-columns
+					 :identifier-case identifier-case
+					 :include-drop include-drop)
      do (pgloader.pgsql:execute pg-dbname sql)
      finally (return nb-tables)))
 
@@ -430,6 +450,7 @@ order by ordinal_position" dbname table-name)))
 			  (include-drop nil)
 			  (create-indexes t)
 			  (reset-sequences t)
+			  (identifier-case :downcase) ; or :quote
 			  (truncate t)
 			  only-tables)
   "Export MySQL data and Import it into PostgreSQL"
@@ -443,6 +464,7 @@ order by ordinal_position" dbname table-name)))
       (with-silent-timing *state* dbname
 			  (format nil "~:[~;DROP then ~]CREATE TABLES" include-drop)
 			  (pgsql-create-tables dbname all-columns
+					       :identifier-case identifier-case
 					       :pg-dbname pg-dbname
 					       :include-drop include-drop)))
 

parser.lisp

@@ -154,7 +154,10 @@ Here's a quick description of the format we're parsing here:
   (def-keyword-rule "name")
   (def-keyword-rule "tables")
   (def-keyword-rule "indexes")
-  (def-keyword-rule "sequences"))
+  (def-keyword-rule "sequences")
+  (def-keyword-rule "downcase")
+  (def-keyword-rule "quote")
+  (def-keyword-rule "identifiers"))
 
 (defrule kw-auto-increment (and "auto_increment" (* (or #\Tab #\Space)))
   (:constant :auto-increment))
@@ -370,12 +373,19 @@ Here's a quick description of the format we're parsing here:
 (defrule option-reset-sequences (and kw-reset kw-sequences)
   (:constant (cons :reset-sequences t)))
 
+(defrule option-identifiers-case (and (or kw-downcase kw-quote) kw-identifiers)
+  (:lambda (id-case)
+    (destructuring-bind (action id) id-case
+      (declare (ignore id))
+      (cons :identifier-case action))))
+
 (defrule mysql-option (or option-workers
 			  option-truncate
 			  option-drop-tables
 			  option-create-tables
 			  option-create-indexes
-			  option-reset-sequences))
+			  option-reset-sequences
+			  option-identifiers-case))
 
 (defrule another-mysql-option (and #\, ignore-whitespace mysql-option)
   (:lambda (source)
@@ -891,10 +901,11 @@ LOAD FROM http:///tapoueh.org/db.t
     LOAD DATABASE FROM mysql://localhost:3306/dbname
         INTO postgresql://localhost/db
 	WITH drop tables,
-		 truncate,
+	     truncate,
-		 create tables,
+	     create tables,
-		 create indexes,
+	     create indexes,
-		 reset sequences
+	     reset sequences,
+             downcase identifiers
 	 SET guc_1 = 'value', guc_2 = 'other value'
 	CAST column col1 to timestamptz drop default using zero-dates-to-null,
              type varchar to text,