<?php
class sql_conversions {
public $actions = array(
"create" => array(
"mysql" => "CREATE TABLE IF NOT EXISTS",
"pgsql" => "CREATE TABLE IF NOT EXISTS",
"sqlite" => "CREATE TABLE IF NOT EXISTS",
),
"delete" => array(
"mysql" => "DELETE",
"pgsql" => "DELETE",
"sqlite" => "DELETE",
),
"find" => array(
"mysql" => "LOCATE( %string%, %substring% )",
"pgsql" => "POSITION( %substring% in %string% )",
"sqlite" => "INSTR( %string%, %substring% )",
),
"select" => array(
"mysql" => "SELECT",
"pgsql" => "SELECT",
"sqlite" => "SELECT",
),
"update" => array(
"mysql" => "UPDATE",
"pgsql" => "UPDATE",
"sqlite" => "UPDATE",
),
);
public $comparisons = array(
"equal" => array(
"mysql" => "=",
"pgsql" => "=",
"sqlite" => "=",
),
"less than" => array(
"mysql" => "<",
"pgsql" => "<",
"sqlite" => "<",
),
"more than" => array(
"mysql" => ">",
"pgsql" => ">",
"sqlite" => ">",
),
"not" => array(
"mysql" => "!",
"pgsql" => "!",
"sqlite" => "!",
),
"not equal" => array(
"mysql" => "!=",
"pgsql" => "!=",
"sqlite" => "!=",
),
"where" => array(
"mysql" => "WHERE",
"pgsql" => "WHERE",
"sqlite" => "WHERE",
),
);
public $data_types = array(
"bool" => array(
"mysql" => "BOOL",
"pgsql" => "BOOL",
"sqlite" => "BOOL",
),
"int" => array(
"mysql" => "INT",
"pgsql" => "INT",
"sqlite" => "INT",
),
"string" => array(
"mysql" => "VARCHAR",
"pgsql" => "VARCHAR",
"sqlite" => "VARCHAR",
),
"text" => array(
"mysql" => "TEXT",
"pgsql" => "TEXT",
"sqlite" => "TEXT",
),
);
public $general = array(
"from" => array(
"mysql" => "FROM",
"pgsql" => "FROM",
"sqlite" => "FROM",
),
);
public $specials = array(
"id" => array(
"mysql" => "NOT NULL AUTO_INCREMENT PRIMARY KEY",
"pgsql" => "SERIAL PRIMARY KEY",
"sqlite" => "SERIAL PRIMARY KEY",
),
"key" => array(
"mysql" => "KEY",
"pgsql" => "KEY",
"sqlite" => "KEY",
),
"auto increment" => array(
"mysql" => "AUTO_INCREMENT",
"pgsql" => "AUTO_INCREMENT",
"sqlite" => "AUTO_INCREMENT",
),
"not null" => array(
"mysql" => "NOT NULL",
"pgsql" => "NOT NULL",
"sqlite" => "NOT NULL",
),
"null" => array(
"mysql" => "NULL",
"pgsql" => "NULL",
"sqlite" => "NULL",
),
"unique" => array(
"mysql" => "CONSTRAINT '%constraint_name%' UNIQUE ( %field_names% )",
"pgsql" => "CONSTRAINT '%constraint_name%' UNIQUE ( %field_names% )",
"sqlite" => "CONSTRAINT '%constraint_name%' UNIQUE ( %field_names% )",
),
);
public $wraps = array(
"close" => array(
"mysql" => "`",
"mssql" => "]",
"pgsql" => "\"",
"sqlite" => "\"",
),
"open" => array(
"mysql" => "`",
"mssql" => "[",
"pgsql" => "\"",
"sqlite" => "\"",
),
);
public function check_field( $needle, $haystack ) {
$field = preg_replace_callback(
// Matches parts to be replaced: '[field]'
'/(\[.*?\])/',
// Callback function. Use 'use()' or define arrays as 'global'
function( $matches ) use ( $haystack ) {
// Remove square brackets from the match
// then use it as variable name
$match = trim( $matches[1], "[]" );
return $match;
},
// Input string to search in.
$needle
);
if( $field === $needle ) {
$field = false;
}
return $field;
}
public function find( $substring, $string ) {
$dbtype = DBTYPE;
$find_string = $this->actions["find"][$dbtype];
$find_string = str_replace( "%string%", $string, $find_string );
$find_string = str_replace( "%substring%", $substring, $find_string );
return $find_string;
}
public function select( $table, $fields, $where ) {
$dbtype = DBTYPE;
$id_close = $this->wraps["close"][$dbtype];
$id_open = $this->wraps["open"][$dbtype];
$query = $this->actions["select"][$dbtype] . " ";
$bind_vars = array();
if( empty( $fields ) ) {
$query .= " * ";
}
foreach( $fields as $field ) {
$query .= $field . ",";
}
$query = substr( $query, 0, -1 );
$query .= " {$this->general["from"][$dbtype]} {$table} ";
if( ! empty( $where ) ) {
$query .= " {$this->comparisons["where"][$dbtype]} ";
}
foreach( $where as $comparison ) {
$comparison_string = "";
//Put a replace of %% symbols with fields and open / close
if( $comparison[0] == "find" ) {
$c1 = $this->check_field( $comparison[1], $fields );
$c2 = $this->check_field( $comparison[2], $fields );
$c3 = $this->check_field( $comparison[3][1], $fields );
if( ! $c1 === FALSE ) {
$c1 = $id_open . $c1 . $id_close;
} else {
$c1 = "?";
array_push( $bind_vars, $comparison[1] );
}
if( ! $c2 === FALSE ) {
$c2 = $id_open . $c2 . $id_close;
} else {
$c2 = "?";
array_push( $bind_vars, $comparison[2] );
}
if( ! $c3 === FALSE ) {
$c3 = $id_open . $c3 . $id_close;
} else {
$c3 = "?";
array_push( $bind_vars, $comparison[3][1] );
}
$c0 = $this->find( $c1, $c2 );
$comparison_string .= "{$c0} {$this->comparisons[$comparison[3][0]][$dbtype]} {$c3}";
} elseif( $comparison[0] == "in" ) {
} elseif( $comparison[0] == "limit" ) {
} else {
if( in_array( $fields, $comparison[1] ) ) {
$comparison[1] = $id_open . $comparison[1] . $id_close;
}
if( in_array( $fields, $comparison[3] ) ) {
$comparison[3] = $id_open . $comparison[3] . $id_close;
}
$comparison_string .= "{$comparison[1]} {$this->$comparisons[$comparison[0]][$dbtype]} {$comparison[2]}";
}
$index = array_search( $comparison, $where );
if( $index ) {
} else {
$query .= "{$comparison_string} ";
}
}
//$query = substr( $query, 0, -1 );
$query .= ";";
return array( $query, $bind_vars );
}
public function table( $table_name, $fields, $attributes ) {
$dbtype = DBTYPE;
$id_close = $this->wraps["close"][$dbtype];
$id_open = $this->wraps["open"][$dbtype];
$query = "{$this->actions["create"][$dbtype]} {$table_name} (";
foreach( $fields as $id => $type ) {
$query .= "{$id} {$this->data_types[$type][$dbtype]}";
foreach( $attributes[$id] as $attribute ) {
$attribute_string = $this->specials["$attribute"][$dbtype];
if( $attribute == "unique" ) {
continue;
}
if( ! strpos( $attribute_string, "%table_name%" ) === FALSE ) {
$attribute_string = str_replace( "%table_name%", $table_name, $attribute_string );
}
if( ! strpos( $attribute_string, "%fields%" ) === FALSE ) {
$fields_string = "";
foreach( $fields as $field ) {
$fields_string .= "{$id_open}field{$id_close},";
}
$fields_string = substr( $fields_string, 0, -1 );
$attribute_string = str_replace( "%fields%", $fields_string, $attribute_string );
}
$query .= " {$attribute_string}";
}
$query .= ",";
}
$id_close = $this->wraps["close"][$dbtype];
$id_open = $this->wraps["open"][$dbtype];
$fields_string = "";
$unique_string = "";
foreach( $attributes as $id => $attributes ) {
if( in_array( "unique", $attributes ) ) {
if( $unique_string == "" ) {
$unique_string = $this->specials["unique"] . ",";
}
$fields_string .= "{$id_open}{$id}{$id_close},";
}
}
$unique_string = str_replace( "%constraint_name%", $fields_string, $unique_string );
$unique_string = str_replace( "%field_names%", $fields_string, $unique_string );
$query .= $unique_string;
$query = substr( $query, 0, -1 );
$query .= ");";
return( $query );
}
public function tables( $tables ) {
$query = "";
foreach( $tables as $table_name => $table_data ) {
$query .= $this->table( $table_name, $table_data["fields"], $table_data["attributes"] );
}
return( $query );
}
public function update( $table, $fields, $where ) {
}
}
?>