improved prepared statements

src/lib/Expr.cpp

@@ -86,6 +86,12 @@ Expr* Expr::makeFunctionRef(char* func_name, Expr* expr, bool distinct) {
 	return e;
 }
 
+Expr* Expr::makePlaceholder(int id) {
+	Expr* e = new Expr(kExprPlaceholder);
+	e->ival = id;
+	return e;
+}
+
 Expr::~Expr() {
 	delete expr;
 	delete expr2;

src/lib/Expr.h

@@ -112,6 +112,8 @@ struct Expr {
 	static Expr* makeColumnRef(char* name);
 	static Expr* makeColumnRef(char* table, char* name);
 	static Expr* makeFunctionRef(char* func_name, Expr* expr, bool distinct);
+
+	static Expr* makePlaceholder(int id);
 };
 
 // Zero initializes an Expr object and assigns it to a space in the heap

src/lib/statements/PrepareStatement.h

@@ -3,6 +3,7 @@
 
 #include "SQLStatement.h"
 #include "SelectStatement.h"
+#include <algorithm>
 
 namespace hsql {
 
@@ -15,15 +16,34 @@ struct PrepareStatement : SQLStatement {
 	PrepareStatement() :
 		SQLStatement(kStmtPrepare),
 		name(NULL),
-		stmt(NULL) {}
+		query(NULL) {}
 	
 	virtual ~PrepareStatement() {
-		delete stmt;
+		delete query;
 		delete name;
 	}
 
+	/**
+	 * @param vector of placeholders that the parser found
+	 *
+	 * When setting the placeholders we need to make sure that they are in the correct order.
+	 * To ensure that, during parsing we store the character position use that to sort the list here.
+	 */
+	void setPlaceholders(std::vector<void*> ph) {
+		for (void* e : ph) {
+			if (e != NULL)
+				placeholders.push_back((Expr*) e);
+		}
+		// Sort by col-id
+		std::sort(placeholders.begin(), placeholders.end(), [](Expr* i, Expr* j) -> bool { return (i->ival < j->ival); });
+
+		// Set the placeholder id on the Expr. This replaces the previously stored column id
+		for (uint i = 0; i < placeholders.size(); ++i) placeholders[i]->ival = i;
+	}
+
 	const char* name;
-	SQLStatement* stmt;
+	SQLStatementList* query;
+	std::vector<Expr*> placeholders;
 };
 
 

src/lib/statements/SQLStatement.h

@@ -6,6 +6,8 @@
 #define __STATEMENT_H__
 
 #include "List.h"
+#include "Expr.h"
+#include <vector>
 
 namespace hsql {
 

src/parser/bison_parser.y

@@ -49,6 +49,7 @@ int yyerror(YYLTYPE* llocp, SQLStatementList** result, yyscan_t scanner, const c
     yylloc->first_line = yylloc->last_line; \
     yylloc->first_column = yylloc->last_column; \
     for(int i = 0; yytext[i] != '\0'; i++) { \
+    	yylloc->total_column++; \
         if(yytext[i] == '\n') { \
             yylloc->last_line++; \
             yylloc->last_column = 0; \
@@ -79,6 +80,7 @@ int yyerror(YYLTYPE* llocp, SQLStatementList** result, yyscan_t scanner, const c
 	@$.last_column = 0;
 	@$.first_line = 0;
 	@$.last_line = 0;
+	@$.total_column = 0;
 	@$.placeholder_id = 0;
 };
 
@@ -220,7 +222,13 @@ int yyerror(YYLTYPE* llocp, SQLStatementList** result, yyscan_t scanner, const c
 
 // Defines our general input.
 input:
-		statement_list opt_semicolon { *result = $1; }
+		prepare_statement {
+			$1->setPlaceholders(yyloc.placeholder_list);
+			*result = new SQLStatementList($1);
+		}
+	|	statement_list opt_semicolon {
+			*result = $1;
+		}
 	;
 
 
@@ -231,7 +239,6 @@ statement_list:
 
 statement:
 		preparable_statement
-	|	prepare_statement { $$ = $1; }
 	;
 
 
@@ -252,10 +259,10 @@ preparable_statement:
  * Prepared Statement
  ******************************/
 prepare_statement:
-		PREPARE IDENTIFIER ':' preparable_statement {
+		PREPARE IDENTIFIER ':' statement_list opt_semicolon {
 			$$ = new PrepareStatement();
 			$$->name = $2;
-			$$->stmt = $4;
+			$$->query = $4;
 		}
 	;
 
@@ -615,7 +622,10 @@ star_expr:
 
 /* TODO: keep list of placeholders */
 placeholder_expr:
-		'?' { $$ = new Expr(kExprPlaceholder); $$->ival = yylloc.placeholder_id++; }
+		'?' {
+			$$ = Expr::makePlaceholder(yylloc.total_column);
+			yyloc.placeholder_list.push_back($$);
+		}
 	;
 
 

src/parser/parser_typedef.h

@@ -1,6 +1,8 @@
 #ifndef __PARSER_TYPEDEF_H__
 #define __PARSER_TYPEDEF_H__
 
+#include <vector>
+
 
 #ifndef YYtypeDEF_YY_SCANNER_T
 #define YYtypeDEF_YY_SCANNER_T
@@ -17,7 +19,12 @@ struct HSQL_CUST_LTYPE {
 	int first_column;
 	int last_line;
 	int last_column;
+
+	int total_column;
+
+	// Placeholder
 	int placeholder_id;
+	std::vector<void*> placeholder_list;
 };
 
 #define HSQL_LTYPE HSQL_CUST_LTYPE

src/sql_tests.cpp

@@ -98,17 +98,36 @@ TEST(DropTableStatementTest) {
 
 
 TEST(PrepareStatementTest) {
-	TEST_PARSE_SINGLE_SQL("PREPARE test: SELECT ?, test FROM t2 WHERE c1 = ?;", kStmtPrepare, PrepareStatement, prep_stmt);
+	TEST_PARSE_SINGLE_SQL("PREPARE test:"
+		"INSERT INTO test VALUES(?);"
+		"SELECT ?, test FROM test WHERE c1 = ?;"
+		"", kStmtPrepare, PrepareStatement, prep_stmt);
 
-	ASSERT_EQ(prep_stmt->stmt->type(), kStmtSelect);
 	ASSERT_STREQ(prep_stmt->name, "test");
+	ASSERT_EQ(prep_stmt->placeholders.size(), 3);
 
-	SelectStatement* stmt = (SelectStatement*) prep_stmt->stmt;
+
-	ASSERT(stmt->select_list->at(0)->isType(kExprPlaceholder));
+	ASSERT_EQ(prep_stmt->query->size(), 2);
-	ASSERT(stmt->where_clause->expr2->isType(kExprPlaceholder));
+	ASSERT_EQ(prep_stmt->query->at(0)->type(), kStmtInsert);
-	// Check IDs of Placehoders
+	ASSERT_EQ(prep_stmt->query->at(1)->type(), kStmtSelect);
-	ASSERT_EQ(stmt->select_list->at(0)->ival, 0);
+
-	ASSERT_EQ(stmt->where_clause->expr2->ival, 1);
+
+	InsertStatement* insert = (InsertStatement*) prep_stmt->query->at(0);
+	SelectStatement* select = (SelectStatement*) prep_stmt->query->at(1);
+
+	ASSERT(insert->values->at(0)->isType(kExprPlaceholder));
+	ASSERT(select->select_list->at(0)->isType(kExprPlaceholder));
+	ASSERT(select->where_clause->expr2->isType(kExprPlaceholder));
+
+	// Check IDs of placeholders
+	ASSERT_EQ(insert->values->at(0)->ival, 0);
+	ASSERT_EQ(insert->values->at(0), prep_stmt->placeholders[0]);
+
+	ASSERT_EQ(select->select_list->at(0)->ival, 1);
+	ASSERT_EQ(select->select_list->at(0), prep_stmt->placeholders[1]);
+
+	ASSERT_EQ(select->where_clause->expr2->ival, 2);
+	ASSERT_EQ(select->where_clause->expr2, prep_stmt->placeholders[2]);
 }