From: stronk7 <stronk7>
Date: Sun, 15 Feb 2009 23:17:56 +0000 (+0000)
Subject: MDL-18244 sql_length() - new cross-db function to calculate the length in chars of... 
X-Git-Url: http://git.mjollnir.org/gw?a=commitdiff_plain;h=7e0db2e20556cd90967597f528613ec182e66229;p=moodle.git

MDL-18244 sql_length() - new cross-db function to calculate the length in chars of any expression ; from 19_STABLE
---

diff --git a/lib/dml/moodle_database.php b/lib/dml/moodle_database.php
index ce8b15b2c7..72ef93c27b 100644
--- a/lib/dml/moodle_database.php
+++ b/lib/dml/moodle_database.php
@@ -1589,6 +1589,15 @@ abstract class moodle_database {
         return $fieldname;
     }
 
+    /**
+     * Returns the SQL text to be used to calculate the length in characters of one expression.
+     * @param string fieldname or expression to calculate its length in characters.
+     * @return string the piece of SQL code to be used in the statement.
+     */
+    public function sql_length($fieldname) {
+        return ' LENGTH(' . $fieldname . ')';
+    }
+
     /**
      * Returns the proper substr() function for each DB.
      * NOTE: this was originally returning only function name
diff --git a/lib/dml/mssql_adodb_moodle_database.php b/lib/dml/mssql_adodb_moodle_database.php
index 53fcac745a..093e2de581 100644
--- a/lib/dml/mssql_adodb_moodle_database.php
+++ b/lib/dml/mssql_adodb_moodle_database.php
@@ -133,6 +133,15 @@ class mssql_adodb_moodle_database extends adodb_moodle_database {
         return ' CONVERT(varchar, ' . $fieldname . ', ' . $numchars . ')';
     }
 
+    /**
+     * Returns the SQL text to be used to calculate the length in characters of one expression.
+     * @param string fieldname or expression to calculate its length in characters.
+     * @return string the piece of SQL code to be used in the statement.
+     */
+    public function sql_length($fieldname) {
+        return ' LEN(' . $fieldname . ')';
+    }
+
     /**
      * Returns the SQL for returning searching one string for the location of another.
      */
diff --git a/lib/dml/mysqli_adodb_moodle_database.php b/lib/dml/mysqli_adodb_moodle_database.php
index 23d4c48719..4c010c84df 100644
--- a/lib/dml/mysqli_adodb_moodle_database.php
+++ b/lib/dml/mysqli_adodb_moodle_database.php
@@ -266,6 +266,15 @@ class mysqli_adodb_moodle_database extends adodb_moodle_database {
         return ' CAST(' . $fieldname . ' AS SIGNED) ';
     }
 
+    /**
+     * Returns the SQL text to be used to calculate the length in characters of one expression.
+     * @param string fieldname or expression to calculate its length in characters.
+     * @return string the piece of SQL code to be used in the statement.
+     */
+    public function sql_length($fieldname) {
+        return ' CHAR_LENGTH(' . $fieldname . ')';
+    }
+
     /**
      * Does this driver suppoer regex syntax when searching
      */
@@ -305,4 +314,4 @@ class mysqli_adodb_moodle_database extends adodb_moodle_database {
 
         return $this->insert_record_raw($table, $cleaned, false, true, true);
     }
-}
\ No newline at end of file
+}
diff --git a/lib/dml/mysqli_native_moodle_database.php b/lib/dml/mysqli_native_moodle_database.php
index 09189025f9..48b2494fcb 100644
--- a/lib/dml/mysqli_native_moodle_database.php
+++ b/lib/dml/mysqli_native_moodle_database.php
@@ -880,6 +880,15 @@ class mysqli_native_moodle_database extends moodle_database {
         return "CONCAT_WS($separator, $s)";
     }
 
+    /**
+     * Returns the SQL text to be used to calculate the length in characters of one expression.
+     * @param string fieldname or expression to calculate its length in characters.
+     * @return string the piece of SQL code to be used in the statement.
+     */
+    public function sql_length($fieldname) {
+        return ' CHAR_LENGTH(' . $fieldname . ')';
+    }
+
     /**
      * Does this driver suppoer regex syntax when searching
      */