SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.299 2007/06/20 16:13:23 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**

/*
** Return the default collation sequence for the expression pExpr. If
** there is no default collation type, return 0.
*/
CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
  CollSeq *pColl = 0;
  if( pExpr ){
    int op;
    pColl = pExpr->pColl;
    op = pExpr->op;
    if( (op==TK_CAST || op==TK_UPLUS) && !pColl ){
      return sqlite3ExprCollSeq(pParse, pExpr->pLeft);
    }
  }
  if( sqlite3CheckCollSeq(pParse, pColl) ){ 
    pColl = 0;
  }
  return pColl;

#
# 2007 June 20
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is making sure collations pass through the
# unary + operator.
#
# $Id: collate8.test,v 1.1 2007/06/20 16:13:23 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_test collate8-1.1 {
  execsql {
    CREATE TABLE t1(a TEXT COLLATE nocase);
    INSERT INTO t1 VALUES('aaa');
    INSERT INTO t1 VALUES('BBB');
    INSERT INTO t1 VALUES('ccc');
    INSERT INTO t1 VALUES('DDD');
    SELECT a FROM t1 ORDER BY a;
  }
} {aaa BBB ccc DDD}
do_test collate8-1.2 {
  execsql {
    SELECT rowid FROM t1 WHERE a<'ccc' ORDER BY 1
  }
} {1 2}
do_test collate8-1.3 {
  execsql {
    SELECT rowid FROM t1 WHERE a<'ccc' COLLATE binary ORDER BY 1
  }
} {1 2 4}
do_test collate8-1.4 {
  execsql {
    SELECT rowid FROM t1 WHERE +a<'ccc' ORDER BY 1
  }
} {1 2}
do_test collate8-1.5 {
  execsql {
    SELECT a FROM t1 ORDER BY +a
  }
} {aaa BBB ccc DDD}

finish_test

set rcsid {$Id: datatype3.tcl,v 1.17 2007/06/20 16:13:23 drh Exp $}
source common.tcl
header {Datatypes In SQLite Version 3}
puts {
<h2>Datatypes In SQLite Version 3</h2>

<h3>1. Storage Classes</h3>

<p>
For binary comparison operators (=, <, >, <= and >=) if either operand is a
column, then the default collation type of the column determines the
collation sequence to use for the comparison. If both operands are columns,
then the collation type for the left operand determines the collation
sequence used. If neither operand is a column, then the BINARY collation
sequence is used.  For the purposes of this paragraph, a column name
preceded by one or more unary "+" operators is considered a column name.
</p>  

<p>
The expression "x BETWEEN y and z" is equivalent to "x &gt;= y AND x &lt;=
z". The expression "x IN (SELECT y ...)" is handled in the same way as the
expression "x = y" for the purposes of determining the collation sequence
to use. The collation sequence used for expressions of the form "x IN (y, z