extended tableref and implemented helper function to print select statements

This commit is contained in:
Pedro 2014-10-23 18:12:03 +02:00
parent c6cd391301
commit eb6444fd2f
7 changed files with 102 additions and 103 deletions

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@ -4,7 +4,7 @@
PARSER = bison PARSER = bison
LIB_FILES = $(PARSER)/$(PARSER)_parser.cpp $(PARSER)/flex_lexer.cpp $(PARSER)/SQLParser.cpp lib/Statement.cpp lib/Expr.cpp LIB_FILES = $(PARSER)/$(PARSER)_parser.cpp $(PARSER)/flex_lexer.cpp $(PARSER)/SQLParser.cpp lib/Statement.cpp lib/Expr.cpp lib/sqlhelper.cpp
TESTS_MAIN = sql_tests.cpp TESTS_MAIN = sql_tests.cpp
TESTS_BIN = bin/tests TESTS_BIN = bin/tests

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@ -71,6 +71,7 @@ typedef void* yyscan_t;
List<char*>* slist; List<char*>* slist;
List<Expr*>* explist; List<Expr*>* explist;
List<TableRef*>* tbllist;
} }
@ -92,11 +93,11 @@ typedef void* yyscan_t;
%type <statement> statement %type <statement> statement
%type <select_statement> select_statement %type <select_statement> select_statement
%type <sval> table_name %type <sval> table_name
%type <table> from_clause table_exp %type <table> from_clause table_ref table_ref_atomic
%type <expr> expr column_name scalar_exp literal %type <expr> expr column_name scalar_exp literal
%type <expr> comparison_predicate predicate search_condition where_clause %type <expr> comparison_predicate predicate search_condition where_clause
%type <slist> table_ref_commalist
%type <explist> expr_list group_clause select_list %type <explist> expr_list group_clause select_list
%type <tbllist> table_ref_commalist
@ -146,7 +147,7 @@ select_list:
from_clause: from_clause:
FROM table_exp { $$ = $2; } FROM table_ref { $$ = $2; }
; ;
@ -162,21 +163,6 @@ group_clause:
; ;
// TODO: comma_list with mixed table names and select statements
table_exp:
table_ref_commalist {
TableRef* t = new TableRef(eTableName);
t->table_names = $1;
$$ = t;
}
| '(' select_statement ')' {
TableRef* t = new TableRef(eTableSelect);
t->stmt = $2;
$$ = t;
}
;
// TODO: multiple predicates // TODO: multiple predicates
search_condition: search_condition:
predicate predicate
@ -214,10 +200,6 @@ column_name:
NAME { $$ = makeColumnRef($1); } NAME { $$ = makeColumnRef($1); }
; ;
table_name:
NAME
| NAME '.' NAME
;
literal: literal:
STRING { $$ = makeStringLiteral($1); } STRING { $$ = makeStringLiteral($1); }
@ -231,20 +213,47 @@ opt_semicolon:
; ;
/******************************
** Lists
******************************/
expr_list: expr_list:
expr { $$ = new List<Expr*>($1); } expr { $$ = new List<Expr*>($1); }
| expr_list ',' expr { $1->push_back($3); $$ = $1; } | expr_list ',' expr { $1->push_back($3); $$ = $1; }
; ;
// TODO: add table_ref to include names and select queries
table_ref_commalist: /******************************
table_name { $$ = new List<char*>($1); } ** Table
| table_ref_commalist ',' table_name { $1->push_back($3); $$ = $1; } ******************************/
table_ref:
table_ref_atomic
| table_ref_atomic ',' table_ref_commalist {
$3->push_back($1);
auto tbl = new TableRef(eTableCrossProduct);
tbl->list = $3;
$$ = tbl;
}
; ;
table_ref_atomic:
table_name {
auto tbl = new TableRef(eTableName);
tbl->name = $1;
$$ = tbl;
}
| '(' select_statement ')' {
auto tbl = new TableRef(eTableSelect);
tbl->stmt = $2;
$$ = tbl;
}
;
table_ref_commalist:
table_ref_atomic { $$ = new List<TableRef*>($1); }
| table_ref_commalist ',' table_ref_atomic { $1->push_back($3); $$ = $1; }
;
table_name:
NAME
| NAME '.' NAME
;
%% %%

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@ -4,5 +4,5 @@ make clean
make tests make tests
./bin/tests ./bin/tests
# make execution make execution
# ./bin/sql_execution "SELECT col1, col2 FROM table GROUP BY col1;" ./bin/sql_execution "SELECT col1, col2 FROM table, (SELECT * FROM a, table, (SELECT * FROM (SELECT * FROM foo))) GROUP BY col1;"

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@ -9,16 +9,20 @@ class SelectStatement;
*/ */
typedef enum { typedef enum {
eTableName, eTableName,
eTableSelect eTableSelect,
eTableCrossProduct
} ETableRefType; } ETableRefType;
typedef struct TableRef TableRef;
struct TableRef { struct TableRef {
TableRef(ETableRefType type) : type(type) {} TableRef(ETableRefType type) : type(type) {}
ETableRefType type; ETableRefType type;
char* name;
SelectStatement* stmt; SelectStatement* stmt;
List<char*>* table_names; List<TableRef*>* list;
}; };

40
src/lib/sqlhelper.cpp Normal file
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@ -0,0 +1,40 @@
#include "sqlhelper.h"
#include <stdio.h>
#include <string>
const char* indent(uint num_indent) { return std::string(num_indent, ' ').c_str(); }
void inprint(int val, uint num_indent) { printf("%s%d\n", indent(num_indent), val); }
void inprint(float val, uint num_indent) { printf("%s%f\n", indent(num_indent), val); }
void inprint(const char* val, uint num_indent) { printf("%s%s\n", indent(num_indent), val); }
void printTableRefInfo(TableRef* table, uint num_indent) {
switch (table->type) {
case eTableName:
inprint(table->name, num_indent);
break;
case eTableSelect:
printSelectStatementInfo(table->stmt, num_indent);
break;
case eTableCrossProduct:
for (TableRef* tbl : table->list->_vector) printTableRefInfo(tbl, num_indent);
break;
}
}
void printSelectStatementInfo(SelectStatement* stmt, uint num_indent) {
inprint("SelectStatement", num_indent);
inprint("Fields:", num_indent+1);
for (Expr* expr : stmt->select_list->_vector) {
switch (expr->type) {
case eExprStar: inprint("*", num_indent+2); break;
case eExprColumnRef: inprint(expr->name, num_indent+2); break;
case eExprLiteralFloat: inprint(expr->float_literal, num_indent+2); break;
case eExprLiteralString: inprint(expr->name, num_indent+2); break;
case eExprFunctionRef: /* todo */ break;
case eExprPredicate: /* todo */ break;
}
}
inprint("Sources:", num_indent+1);
printTableRefInfo(stmt->from_table, num_indent+2);
}

11
src/lib/sqlhelper.h Normal file
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@ -0,0 +1,11 @@
#ifndef __SQLHELPER_H__
#define __SQLHELPER_H__
#include "Statement.h"
void printSelectStatementInfo(SelectStatement* stmt, uint num_indent);
#endif

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@ -1,11 +1,8 @@
#include "SQLParser.h"
#include <stdio.h> #include <stdio.h>
#include <string> #include <string>
#include "lib/sqlhelper.h"
typedef int* Table; #include "SQLParser.h"
Table executeSelect(SelectStatement* stmt);
int main(int argc, char *argv[]) { int main(int argc, char *argv[]) {
if (argc <= 1) { if (argc <= 1) {
@ -13,8 +10,6 @@ int main(int argc, char *argv[]) {
return -1; return -1;
} }
// Statement *stmt = NULL;
for (int n = 1; n < argc; ++n) { for (int n = 1; n < argc; ++n) {
char* sql = argv[n]; char* sql = argv[n];
@ -27,7 +22,7 @@ int main(int argc, char *argv[]) {
} }
if (stmt->type == eSelect) { if (stmt->type == eSelect) {
executeSelect((SelectStatement*)stmt); printSelectStatementInfo((SelectStatement*) stmt, 0);
} else { } else {
fprintf(stderr, "Only Supporting Select Statements!\n"); fprintf(stderr, "Only Supporting Select Statements!\n");
} }
@ -35,63 +30,3 @@ int main(int argc, char *argv[]) {
return 0; return 0;
} }
// Dummy Database
int NUM_COLUMNS = 4;
int NUM_ROWS = 100;
int TABLE[] = {40,59,8,7,74,28,7,10,15,17,2,20,15,82,41,20,25,72,89,67,74,0,70,31,67,75,74,30,0,45,82,6,9,35,73,83,13,46,39,45,28,34,11,41,20,30,72,78,51,36,32,71,16,70,39,88,59,25,0,68,73,54,0,4,7,35,19,4,6,23,30,25,51,31,52,14,65,95,95,85,94,90,65,35,51,64,68,44,80,7,78,23,99,30,17,72,8,22,40,47,15,30,9,51,77,9,67,94,15,69,49,21,51,99,91,36,5,91,69,55,36,36,74,63,1,87,24,67,51,52,21,10,60,37,6,43,53,4,25,35,19,4,61,61,16,83,9,69,32,46,36,74,96,47,90,27,48,48,79,95,55,64,48,40,42,77,33,18,36,80,23,24,1,75,2,63,9,23,17,99,82,56,9,92,17,94,76,35,28,86,61,58,38,61,16,4,69,61,51,33,53,23,6,48,81,62,46,51,61,34,97,100,53,7,41,61,45,15,46,91,85,29,73,75,39,24,99,38,0,32,68,23,76,25,62,40,58,67,85,33,18,51,70,45,27,62,30,89,85,53,87,91,61,37,33,69,2,2,9,24,23,55,45,76,0,59,72,12,75,5,10,52,59,32,34,24,86,72,97,2,5,4,0,70,6,98,29,22,11,69,74,90,19,12,68,7,55,22,70,83,20,72,88,61,46,38,98,4,15,63,14,42,16,94,100,33,58,65,53,56,26,94,63,80,88,22,49,20,57,81,89,30,82,83,62,87,21,91,36,98,78,53,24,69,60,31,24,71,9,95,94,30,42,35,97,56,51,14,31,0,73,80,11,83,77,9,51,93,37,16,41,99,24,93,100,12,23,59,61,36,70,69,100,4,14,73,47,81,54,44,12,34,14,55,95,19,79,95,77,69};
int getValue(int col, int row) {
return TABLE[row*NUM_COLUMNS+col];
}
int getValue(std::string col_name, int row) {
if (col_name.compare("col1") == 0) return getValue(0, row);
if (col_name.compare("col2") == 0) return getValue(1, row);
if (col_name.compare("col3") == 0) return getValue(2, row);
if (col_name.compare("col4") == 0) return getValue(3, row);
return 0;
}
Table executeGroupBySelect(SelectStatement* stmt, Table source) {
fprintf(stderr, "GROUP BY not yet implemented!\n");
return NULL;
}
Table executeSelect(SelectStatement* stmt) {
// Step 1:
// Determine source table
TableRef* from_table = stmt->from_table;
Table source;
if (from_table->type == eTableSelect) {
// Nested Select Statements
source = executeSelect(from_table->stmt);
} else if (from_table->type == eTableName) {
if (from_table->table_names->size() == 1) {
if (std::string(from_table->table_names->at(0)).compare("table") == 0) {
source = TABLE;
} else {
fprintf(stderr, "Couldn't find table!\n");
return NULL;
}
} else {
// Cross product of table
fprintf(stderr, "We're not supporting cross product of tables atm.\n");
return NULL;
}
}
// Step 2
// Check if group by
if (stmt->group_by != NULL) {
return executeGroupBySelect(stmt, source);
}
return NULL;
}