>From 20aeb9470d783dd827147136e530fca23cd9810d Mon Sep 17 00:00:00 2001
From: Holger Hans Peter Freyther <address@hidden>
Date: Fri, 8 Apr 2011 14:09:37 +0200
Subject: [PATCH 3/4] dbd-postgres: Allow to execute queries with parameters

This only supports the PostgreSQL way of specifying parameters
using the $1 $2 $3 parameters. It does not support named bindings
or such. This makes going from SQLite to Postgres a lot harder. The
parameters must be provided as string, there is no type conversion
done on this level.
---
 packages/dbd-postgresql/ChangeLog     |    5 ++++
 packages/dbd-postgresql/Connection.st |   38 +++++++++++++++++++++++++++++++++
 packages/dbd-postgresql/Statement.st  |   21 +++++++++++++----
 3 files changed, 59 insertions(+), 5 deletions(-)

diff --git a/packages/dbd-postgresql/ChangeLog b/packages/dbd-postgresql/ChangeLog
index ea768b5..0ca6d3b 100644
--- a/packages/dbd-postgresql/ChangeLog
+++ b/packages/dbd-postgresql/ChangeLog
@@ -1,5 +1,10 @@
 2011-04-08  Holger Hans Peter Freyther  <address@hidden>
 
+	* Statements.st: Implement executeWithAll:
+	* Connection.st: Invoke PQexecParams.
+
+2011-04-08  Holger Hans Peter Freyther  <address@hidden>
+
 	* Statement.st: New.
 
 2011-01-26  Stefan Schmiedl  <address@hidden>
diff --git a/packages/dbd-postgresql/Connection.st b/packages/dbd-postgresql/Connection.st
index f23d3f2..202e604 100644
--- a/packages/dbd-postgresql/Connection.st
+++ b/packages/dbd-postgresql/Connection.st
@@ -188,6 +188,44 @@ CObject subclass: PQConnection [
     exec: aSqlStatement [
         <cCall: 'PQexec' returning: #{PQResultSet} args: #(#self #string)>
     ]
+
+    "Executing SQL with params"
+    exec: aSqlStatement with: params [
+        | par |
+
+        "Sanity check before we do memory allocations in C"
+        (params allSatisfy: [:el | el isString]) ifFalse: [
+            ^ self error: 'All parameters must be strings here'].
+
+        "Convert the params into an array of C-Strings."
+        par := CStringType new: params size.
+        1 to: params size do: [:each |
+            par at: each - 1 put: (params at: each)].
+
+        [^ self
+            exec_params:aSqlStatement
+            n_par: params size
+            types: nil
+            values: par
+            lengths: nil
+            formats: nil
+            res: 0
+        ] ensure: [
+            "Free the memory we allocated"
+
+            0 to: params size - 1 do: [:each |
+                (par derefAt: (each * CStringType sizeof) type: CObjectType) free
+            ].
+
+            par free.
+        ]
+    ]
+
+    exec_params: cmd n_par: parAms types: types values: vals lengths: l formats: f res: r [
+        <category: 'private'>
+        <cCall: 'PQexecParams' returning: #{PQResultSet}
+            args: #(#self #string #int #cObject #cObject #cObject #cObject #int)>
+    ]
 ]
 
 
diff --git a/packages/dbd-postgresql/Statement.st b/packages/dbd-postgresql/Statement.st
index c9cfaa7..9335989 100644
--- a/packages/dbd-postgresql/Statement.st
+++ b/packages/dbd-postgresql/Statement.st
@@ -53,6 +53,8 @@ now the ability to execute commands with binding.'>
 
     queryString: aSQLQuery [
         <category: 'accessing'>
+        "In PostgreSQL one can use $1 for binding parameters with the
+         executeWithAll:. The parameters must be all strings."
         queryString := aSQLQuery.
     ]
 
@@ -63,17 +65,26 @@ now the ability to execute commands with binding.'>
         ^isSelect
     ]
 
+    checkResult: aRes [
+        <category: 'private'>
+        self isSelect
+            ifTrue:  [aRes checkStatusForSelect]
+            ifFalse: [aRes checkStatusForDo].
+        ^ aRes
+    ]
+
     execute [
         <category: 'querying'>
         | res |
         res := PGResultSet new: (dbHandle exec: queryString).
-        self isSelect
-            ifTrue:  [res checkStatusForSelect]
-            ifFalse: [res checkStatusForDo].
-        ^ res
+        ^ self checkResult: res.
     ]
 
     executeWithAll: aParams [
-        self notYetImplemented
+        | res |
+        "In PostgreSQL one can use $1 for binding parameters with the
+         executeWithAll:. The parameters must be all strings."
+        res := PGResultSet new: (dbHandle exec: queryString with: aParams).
+        ^ self checkResult: res.
     ]
 ]
-- 
1.7.4