Index: src/vdbe.c ================================================================== --- src/vdbe.c +++ src/vdbe.c @@ -3692,19 +3692,17 @@ pFree = 0; /* Not needed. Only used to suppress a compiler warning. */ if( pOp->p4.i>0 ){ r.pKeyInfo = pC->pKeyInfo; r.nField = (u16)pOp->p4.i; r.aMem = pIn3; + for(ii=0; iip3+i, &r.aMem[i]); - } - } + if( ii ) REGISTER_TRACE(pOp->p3+ii, &r.aMem[ii]); #endif + } r.flags = UNPACKED_PREFIX_MATCH; pIdxKey = &r; }else{ pIdxKey = sqlite3VdbeAllocUnpackedRecord( pC->pKeyInfo, aTempRec, sizeof(aTempRec), &pFree Index: test/distinct.test ================================================================== --- test/distinct.test +++ test/distinct.test @@ -194,7 +194,32 @@ do_test 3.1 { regexp {OpenEphemeral} [db eval { EXPLAIN SELECT DISTINCT a, b FROM t3 ORDER BY +a, +b; }] } {0} + +#------------------------------------------------------------------------- +# Ticket [fccbde530a6583bf2748400919f1603d5425995c] (2014-01-08) +# The logic that computes DISTINCT sometimes thinks that a zeroblob() +# and a blob of all zeros are different when they should be the same. +# +do_execsql_test 4.1 { + DROP TABLE IF EXISTS t1; + DROP TABLE IF EXISTS t2; + CREATE TABLE t1(a INTEGER); + INSERT INTO t1 VALUES(3); + INSERT INTO t1 VALUES(2); + INSERT INTO t1 VALUES(1); + INSERT INTO t1 VALUES(2); + INSERT INTO t1 VALUES(3); + INSERT INTO t1 VALUES(1); + CREATE TABLE t2(x); + INSERT INTO t2 + SELECT DISTINCT + CASE a WHEN 1 THEN x'0000000000' + WHEN 2 THEN zeroblob(5) + ELSE 'xyzzy' END + FROM t1; + SELECT quote(x) FROM t2 ORDER BY 1; +} {'xyzzy' X'0000000000'} finish_test