Abstracted FROM table listing in Active Record for databases that do not support parenthetic grouping of tables to explicitly define operator precedence
diff --git a/system/database/DB_active_rec.php b/system/database/DB_active_rec.php
index 1ad4f3d..37bf9ed 100644
--- a/system/database/DB_active_rec.php
+++ b/system/database/DB_active_rec.php
@@ -1343,7 +1343,7 @@
if (count($this->ar_from) > 0)
{
$sql .= "\nFROM ";
- $sql .= '(' . implode(', ', $this->ar_from) . ')';
+ $sql .= $this->_from_tables($this->ar_from);
}
if (count($this->ar_join) > 0)
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index e0c4db7..ad747d4 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -439,6 +439,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return implode(', ', $tables);
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index 6e53537..f002572 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -480,6 +480,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return '('.implode(', ', $tables).')';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index d645cc8..b2e97f9 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -474,6 +474,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return '('.implode(', ', $tables).')';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data
diff --git a/system/database/drivers/oci8/oci8_driver.php b/system/database/drivers/oci8/oci8_driver.php
index 99f7d57..ddc0fba 100644
--- a/system/database/drivers/oci8/oci8_driver.php
+++ b/system/database/drivers/oci8/oci8_driver.php
@@ -585,6 +585,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return '('.implode(', ', $tables).')';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data
diff --git a/system/database/drivers/odbc/odbc_driver.php b/system/database/drivers/odbc/odbc_driver.php
index 604dd77..03c0e6a 100644
--- a/system/database/drivers/odbc/odbc_driver.php
+++ b/system/database/drivers/odbc/odbc_driver.php
@@ -450,6 +450,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return '('.implode(', ', $tables).')';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data
diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 96cf2df..20f9165 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -470,6 +470,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return '('.implode(', ', $tables).')';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data
diff --git a/system/database/drivers/sqlite/sqlite_driver.php b/system/database/drivers/sqlite/sqlite_driver.php
index 9cc69bb..38febca 100644
--- a/system/database/drivers/sqlite/sqlite_driver.php
+++ b/system/database/drivers/sqlite/sqlite_driver.php
@@ -466,6 +466,28 @@
// --------------------------------------------------------------------
/**
+ * From Tables
+ *
+ * This function implicitly groups FROM tables so there is no confusion
+ * about operator precedence in harmony with SQL standards
+ *
+ * @access public
+ * @param type
+ * @return type
+ */
+ function _from_tables($tables)
+ {
+ if (! is_array($tables))
+ {
+ $tables = array($tables);
+ }
+
+ return '('.implode(', ', $tables).')';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Insert statement
*
* Generates a platform-specific insert string from the supplied data