1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
|
.\" Title: \fBmysql\fR
.\" Author:
.\" Generator: DocBook XSL Stylesheets v1.70.1 <http://docbook.sf.net/>
.\" Date: 05/23/2009
.\" Manual: Drizzle Database System
.\" Source: Drizzle
.\"
.TH "\fBDRIZZLE\fR" "1" "05/23/2009" "Drizzle" "Drizzle Database System"
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.SH "NAME"
drizzle \- the Drizzle command\-line tool
.SH "SYNOPSIS"
.HP 24
\fBdrizzle [\fR\fB\fIoptions\fR\fR\fB] \fR\fB\fIdb_name\fR\fR
.SH "DESCRIPTION"
.PP
\fBdrizzle\fR
is a simple SQL shell (with GNU
readline
capabilities). It supports interactive and non\-interactive use. When used interactively, query results are presented in an ASCII\-table format. When used non\-interactively (for example, as a filter), the result is presented in tab\-separated format. The output format can be changed using command options.
.PP
If you have problems due to insufficient memory for large result sets, use the
\fB\-\-quick\fR
option. This forces
\fBdrizzle\fR
to retrieve results from the server a row at a time rather than retrieving the entire result set and buffering it in memory before displaying it.
.PP
Using
\fBdrizzle\fR
is very easy. Invoke it from the prompt of your command interpreter as follows:
.sp
.RS 3n
.nf
shell> \fBdrizzle \fR\fB\fIdb_name\fR\fR
.fi
.RE
.PP
Or:
.sp
.RS 3n
.nf
shell> \fBdrizzle \-\-user=\fR\fB\fIuser_name\fR\fR\fB \-\-password=\fR\fB\fIyour_password\fR\fR\fB \fR\fB\fIdb_name\fR\fR
.fi
.RE
.PP
Then type an SQL statement, end it with
\(lq;\(rq,
\\g, or
\\G
and press Enter.
.PP
Typing Control\-C causes
\fBdrizzle\fR
to attempt to kill the current statement. If this cannot be done, or Control\-C is typed again before the statement is killed,
\fBdrizzle\fR
exits.
.PP
You can execute SQL statements in a script file (batch file) like this:
.sp
.RS 3n
.nf
shell> \fBdrizzle \fR\fB\fIdb_name\fR\fR\fB < \fR\fB\fIscript.sql\fR\fR\fB > \fR\fB\fIoutput.tab\fR\fR
.fi
.RE
.SH "\fBDRIZZLE\fR OPTIONS"
.PP
\fBdrizzle\fR
supports the options in the following list.
.TP 3n
\(bu
\fB\-\-help\fR,
\fB\-?\fR
.sp
Display a help message and exit.
.TP 3n
\(bu
\fB\-\-auto\-rehash\fR
.sp
Enable automatic rehashing. This option is on by default, which enables database, table, and column name completion. Use
\fB\-\-disable\-auto\-rehash\fR
to disable rehashing. That causes
\fBdrizzle\fR
to start faster, but you must issue the
rehash
command if you want to use name completion.
.sp
To complete a name, enter the first part and press Tab. If the name is unambiguous,
\fBdrizzle\fR
completes it. Otherwise, you can press Tab again to see the possible names that begin with what you have typed so far. Completion does not occur if there is no default database.
.TP 3n
\(bu
\fB\-\-auto\-vertical\-output\fR
.sp
Causes result sets to be displayed vertically if they are too wide for the current window, and using normal tabular format otherwise. (This applies to statements terminated by
;
or
\\G.) This option was added in Drizzle 6.0.4.
.TP 3n
\(bu
\fB\-\-batch\fR,
\fB\-B\fR
.sp
Print results using tab as the column separator, with each row on a new line. With this option,
\fBdrizzle\fR
does not use the history file.
.sp
Batch mode results in non\-tabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the
\fB\-\-raw\fR
option.
.TP 3n
\(bu
\fB\-\-character\-sets\-dir=\fR\fB\fIpath\fR\fR
.sp
The directory where character sets are installed. See
Section\ 9.2, \(lqThe Character Set Used for Data and Sorting\(rq.
.TP 3n
\(bu
\fB\-\-column\-names\fR
.sp
Write column names in results.
.TP 3n
\(bu
\fB\-\-column\-type\-info\fR,
\fB\-m\fR
.sp
Display result set metadata.
.TP 3n
\(bu
\fB\-\-comments\fR,
\fB\-c\fR
.sp
Whether to preserve comments in statements sent to the server. The default is \-\-skip\-comments (discard comments), enable with \-\-comments (preserve comments). This option was added in Drizzle 6.0.4.
.TP 3n
\(bu
\fB\-\-compress\fR,
\fB\-C\fR
.sp
Compress all information sent between the client and the server if both support compression.
.TP 3n
\(bu
\fB\-\-database=\fR\fB\fIdb_name\fR\fR,
\fB\-D \fR\fB\fIdb_name\fR\fR
.sp
The database to use. This is useful primarily in an option file.
.TP 3n
\(bu
\fB\-\-debug\-check\fR
.sp
Print some debugging information when the program exits.
.TP 3n
\(bu
\fB\-\-debug\-info\fR,
\fB\-T\fR
.sp
Print debugging information and memory and CPU usage statistics when the program exits.
.TP 3n
\(bu
\fB\-\-delimiter=\fR\fB\fIstr\fR\fR
.sp
Set the statement delimiter. The default is the semicolon character (\(lq;\(rq).
.TP 3n
\(bu
\fB\-\-disable\-named\-commands\fR
.sp
Disable named commands. Use the
\\*
form only, or use named commands only at the beginning of a line ending with a semicolon (\(lq;\(rq).
\fBdrizzle\fR
starts with this option
\fIenabled\fR
by default. However, even with this option, long\-format commands still work from the first line. See
the section called \(lq\fBMYSQL\fR COMMANDS\(rq.
.TP 3n
\(bu
\fB\-\-execute=\fR\fB\fIstatement\fR\fR,
\fB\-e \fR\fB\fIstatement\fR\fR
.sp
Execute the statement and quit. The default output format is like that produced with
\fB\-\-batch\fR. See
Section\ 4.2.3.1, \(lqUsing Options on the Command Line\(rq, for some examples.
.TP 3n
\(bu
\fB\-\-force\fR,
\fB\-f\fR
.sp
Continue even if an SQL error occurs.
.TP 3n
\(bu
\fB\-\-host=\fR\fB\fIhost_name\fR\fR,
\fB\-h \fR\fB\fIhost_name\fR\fR
.sp
Connect to the Drizzle server on the given host.
.TP 3n
\(bu
\fB\-\-html\fR,
\fB\-H\fR
.sp
Produce HTML output.
.TP 3n
\(bu
\fB\-\-ignore\-spaces\fR,
\fB\-i\fR
.sp
Ignore spaces after function names. The effect of this is described in the discussion for the
IGNORE_SPACE
SQL mode (see
Section\ 5.1.7, \(lqServer SQL Modes\(rq).
.TP 3n
\(bu
\fB\-\-line\-numbers\fR
.sp
Write line numbers for errors. Disable this with
\fB\-\-skip\-line\-numbers\fR.
.TP 3n
\(bu
\fB\-\-local\-infile[={0|1}]\fR
.sp
Enable or disable
LOCAL
capability for
LOAD DATA INFILE. With no value, the option enables
LOCAL. The option may be given as
\fB\-\-local\-infile=0\fR
or
\fB\-\-local\-infile=1\fR
to explicitly disable or enable
LOCAL. Enabling
LOCAL
has no effect if the server does not also support it.
.TP 3n
\(bu
\fB\-\-named\-commands\fR,
\fB\-G\fR
.sp
Enable named
\fBdrizzle\fR
commands. Long\-format commands are allowed, not just short\-format commands. For example,
quit
and
\\q
both are recognized. Use
\fB\-\-skip\-named\-commands\fR
to disable named commands. See
the section called \(lq\fBMYSQL\fR COMMANDS\(rq.
.TP 3n
\(bu
\fB\-\-no\-auto\-rehash\fR,
\fB\-A\fR
.sp
Deprecated form of
\fB\-skip\-auto\-rehash\fR. Use
\fB\-\-disable\-auto\-rehash\fR
instead. See the description for
\fB\-\-auto\-rehash\fR.
.TP 3n
\(bu
\fB\-\-no\-beep\fR,
\fB\-b\fR
.sp
Do not beep when errors occur.
.TP 3n
\(bu
\fB\-\-no\-named\-commands\fR,
\fB\-g\fR
.sp
Deprecated, use
\fB\-\-disable\-named\-commands\fR
instead.
.TP 3n
\(bu
\fB\-\-no\-pager\fR
.sp
Deprecated form of
\fB\-\-skip\-pager\fR. See the
\fB\-\-pager\fR
option.
.TP 3n
\(bu
\fB\-\-no\-tee\fR
.sp
Do not copy output to a file.
the section called \(lq\fBMYSQL\fR COMMANDS\(rq, discusses tee files further.
.TP 3n
\(bu
\fB\-\-one\-database\fR,
\fB\-o\fR
.sp
Ignore statements except those for the default database named on the command line. This is useful for skipping updates to other databases in the binary log.
.TP 3n
\(bu
\fB\-\-pager[=\fR\fB\fIcommand\fR\fR\fB]\fR
.sp
Use the given command for paging query output. If the command is omitted, the default pager is the value of your
PAGER
environment variable. Valid pagers are
\fBless\fR,
\fBmore\fR,
\fBcat [> filename]\fR, and so forth. This option works only on Unix. It does not work in batch mode. To disable paging, use
\fB\-\-skip\-pager\fR.
the section called \(lq\fBMYSQL\fR COMMANDS\(rq, discusses output paging further.
.TP 3n
\(bu
\fB\-\-password[=\fR\fB\fIpassword\fR\fR\fB]\fR,
\fB\-P[\fR\fB\fIpassword\fR\fR\fB]\fR
.sp
The password to use when connecting to the server. If you use the short option form (\fB\-p\fR), you
\fIcannot\fR
have a space between the option and the password. If you omit the
\fIpassword\fR
value following the
\fB\-\-password\fR
or
\fB\-p\fR
option on the command line, you are prompted for one.
.sp
Specifying a password on the command line should be considered insecure. See
Section\ 5.5.6.2, \(lqEnd\-User Guidelines for Password Security\(rq.
.TP 3n
\(bu
\fB\-\-pipe\fR,
\fB\-W\fR
.sp
On Windows, connect to the server via a named pipe. This option applies only for connections to a local server, and only if the server supports named\-pipe connections.
.TP 3n
\(bu
\fB\-\-port=\fR\fB\fIport_num\fR\fR,
\fB\-p \fR\fB\fIport_num\fR\fR
.sp
The TCP/IP port number to use for the connection.
.TP 3n
\(bu
\fB\-\-prompt=\fR\fB\fIformat_str\fR\fR
.sp
Set the prompt to the specified format. The default is
drizzle>. The special sequences that the prompt can contain are described in
the section called \(lq\fBMYSQL\fR COMMANDS\(rq.
.TP 3n
\(bu
\fB\-\-protocol={TCP|SOCKET|PIPE|MEMORY}\fR
.sp
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the allowable values, see
Section\ 4.2.2, \(lqConnecting to the Drizzle Server\(rq.
.TP 3n
\(bu
\fB\-\-quick\fR,
\fB\-q\fR
.sp
Do not cache each query result, print each row as it is received. This may slow down the server if the output is suspended. With this option,
\fBdrizzle\fR
does not use the history file.
.TP 3n
\(bu
\fB\-\-raw\fR,
\fB\-r\fR
.sp
For tabular output, the
\(lqboxing\(rq
around columns enables one column value to be distinguished from another. For non\-tabular output (such as is produced in batch mode or when the
\fB\-\-batch\fR
or
\fB\-\-silent\fR
option is given), special characters are escaped in the output so they can be identified easily. Newline, tab,
NUL, and backslash are written as
\\n,
\\t,
\\0, and
\\\\. The
\fB\-\-raw\fR
option disables this character escaping.
.sp
The following example demonstrates tabular versus non\-tabular output and the use of raw mode to disable escaping:
.sp
.RS 3n
.nf
% \fBdrizzle\fR
drizzle> SELECT CHAR(92);
+\-\-\-\-\-\-\-\-\-\-+
| CHAR(92) |
+\-\-\-\-\-\-\-\-\-\-+
| \\ |
+\-\-\-\-\-\-\-\-\-\-+
% \fBdrizzle \-s\fR
drizzle> SELECT CHAR(92);
CHAR(92)
\\\\
% \fBdrizzle \-s \-r\fR
drizzle> SELECT CHAR(92);
CHAR(92)
\\
.fi
.RE
.TP 3n
\(bu
\fB\-\-reconnect\fR
.sp
If the connection to the server is lost, automatically try to reconnect. A single reconnect attempt is made each time the connection is lost. To suppress reconnection behavior, use
\fB\-\-skip\-reconnect\fR.
.TP 3n
\(bu
\fB\-\-safe\-updates\fR,
\fB\-\-i\-am\-a\-dummy\fR,
\fB\-U\fR
.sp
Allow only those
UPDATE
and
DELETE
statements that specify which rows to modify by using key values. If you have set this option in an option file, you can override it by using
\fB\-\-safe\-updates\fR
on the command line. See
the section called \(lq\fBMYSQL\fR TIPS\(rq, for more information about this option.
.TP 3n
\(bu
\fB\-\-secure\-auth\fR
.sp
Do not send passwords to the server in old (pre\-4.1.1) format. This prevents connections except for servers that use the newer password format.
.TP 3n
\(bu
\fB\-\-show\-warnings\fR
.sp
Cause warnings to be shown after each statement if there are any. This option applies to interactive and batch mode.
.TP 3n
\(bu
\fB\-\-sigint\-ignore\fR
.sp
Ignore
SIGINT
signals (typically the result of typing Control\-C).
.TP 3n
\(bu
\fB\-\-silent\fR,
\fB\-s\fR
.sp
Silent mode. Produce less output. This option can be given multiple times to produce less and less output.
.sp
This option results in non\-tabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the
\fB\-\-raw\fR
option.
.TP 3n
\(bu
\fB\-\-skip\-column\-names\fR,
\fB\-N\fR
.sp
Do not write column names in results. The short format,
\fB\-N\fR
is deprecated, use the long format instead.
.TP 3n
\(bu
\fB\-\-skip\-line\-numbers\fR,
\fB\-L\fR
.sp
Do not write line numbers for errors. Useful when you want to compare result files that include error messages. The short format,
\fB\-L\fR
is deprecated, use the long format instead.
.TP 3n
\(bu
\fB\-\-socket=\fR\fB\fIpath\fR\fR,
\fB\-S \fR\fB\fIpath\fR\fR
.sp
For connections to
localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use.
.TP 3n
\(bu
\fB\-\-ssl*\fR
.sp
Options that begin with
\fB\-\-ssl\fR
specify whether to connect to the server via SSL and indicate where to find SSL keys and certificates. See
Section\ 5.5.7.3, \(lqSSL Command Options\(rq.
.TP 3n
\(bu
\fB\-\-table\fR,
\fB\-t\fR
.sp
Display output in table format. This is the default for interactive use, but can be used to produce table output in batch mode.
.TP 3n
\(bu
\fB\-\-tee=\fR\fB\fIfile_name\fR\fR
.sp
Append a copy of output to the given file. This option does not work in batch mode.
the section called \(lq\fBMYSQL\fR COMMANDS\(rq, discusses tee files further.
.TP 3n
\(bu
\fB\-\-unbuffered\fR,
\fB\-n\fR
.sp
Flush the buffer after each query.
.TP 3n
\(bu
\fB\-\-user=\fR\fB\fIuser_name\fR\fR,
\fB\-u \fR\fB\fIuser_name\fR\fR
.sp
The Drizzle user name to use when connecting to the server.
.TP 3n
\(bu
\fB\-\-verbose\fR,
\fB\-v\fR
.sp
Verbose mode. Produce more output about what the program does. This option can be given multiple times to produce more and more output. (For example,
\fB\-v \-v \-v\fR
produces table output format even in batch mode.)
.TP 3n
\(bu
\fB\-\-version\fR,
\fB\-V\fR
.sp
Display version information and exit.
.TP 3n
\(bu
\fB\-\-vertical\fR,
\fB\-E\fR
.sp
Print query output rows vertically (one line per column value). Without this option, you can specify vertical output for individual statements by terminating them with
\\G.
.TP 3n
\(bu
\fB\-\-wait\fR,
\fB\-w\fR
.sp
If the connection cannot be established, wait and retry instead of aborting.
.TP 3n
.PP
You can also set the following variables by using
\fB\-\-\fR\fB\fIvar_name\fR\fR\fB=\fR\fB\fIvalue\fR\fR. The
\fB\-\-set\-variable\fR
format is deprecated.
.TP 3n
\(bu
connect_timeout
.sp
The number of seconds before connection timeout. (Default value is
0.)
.TP 3n
\(bu
max_allowed_packet
.sp
The maximum packet length to send to or receive from the server. (Default value is 16MB.)
.TP 3n
\(bu
max_join_size
.sp
The automatic limit for rows in a join when using
\fB\-\-safe\-updates\fR. (Default value is 1,000,000.)
.TP 3n
\(bu
net_buffer_length
.sp
The buffer size for TCP/IP and socket communication. (Default value is 16KB.)
.TP 3n
\(bu
select_limit
.sp
The automatic limit for
SELECT
statements when using
\fB\-\-safe\-updates\fR. (Default value is 1,000.)
.sp
.RE
.PP
On Unix, the
\fBmysql\fR
client writes a record of executed statements to a history file. By default, this file is named
\fI.mysql_history\fR
and is created in your home directory. To specify a different file, set the value of the
MYSQL_HISTFILE
environment variable.
.PP
The
\fI.mysql_history\fR
should be protected with a restrictive access mode because sensitive information might be written to it, such as the text of SQL statements that contain passwords. See
Section\ 5.5.6.2, \(lqEnd\-User Guidelines for Password Security\(rq.
.PP
If you do not want to maintain a history file, first remove
\fI.mysql_history\fR
if it exists, and then use either of the following techniques:
.TP 3n
\(bu
Set the
MYSQL_HISTFILE
variable to
\fI/dev/null\fR. To cause this setting to take effect each time you log in, put the setting in one of your shell's startup files.
.TP 3n
\(bu
Create
\fI.mysql_history\fR
as a symbolic link to
\fI/dev/null\fR:
.sp
.RS 3n
.nf
shell> \fBln \-s /dev/null $HOME/.mysql_history\fR
.fi
.RE
You need do this only once.
.SH "\fBMYSQL\fR COMMANDS"
.PP
\fBmysql\fR
sends each SQL statement that you issue to the server to be executed. There is also a set of commands that
\fBmysql\fR
itself interprets. For a list of these commands, type
help
or
\\h
at the
mysql>
prompt:
.sp
.RS 3n
.nf
mysql> \fBhelp\fR
List of all Drizzle commands:
Note that all text commands must be first on line and end with ';'
? (\\?) Synonym for `help'.
clear (\\c) Clear command.
connect (\\r) Reconnect to the server. Optional arguments are db and host.
delimiter (\\d) Set statement delimiter.
edit (\\e) Edit command with $EDITOR.
ego (\\G) Send command to mysql server, display result vertically.
exit (\\q) Exit mysql. Same as quit.
go (\\g) Send command to mysql server.
help (\\h) Display this help.
nopager (\\n) Disable pager, print to stdout.
notee (\\t) Don't write into outfile.
pager (\\P) Set PAGER [to_pager]. Print the query results via PAGER.
print (\\p) Print current command.
prompt (\\R) Change your mysql prompt.
quit (\\q) Quit mysql.
rehash (\\#) Rebuild completion hash.
source (\\.) Execute an SQL script file. Takes a file name as an argument.
status (\\s) Get status information from the server.
system (\\!) Execute a system shell command.
tee (\\T) Set outfile [to_outfile]. Append everything into given
outfile.
use (\\u) Use another database. Takes database name as argument.
charset (\\C) Switch to another charset. Might be needed for processing
binlog with multi\-byte charsets.
warnings (\\W) Show warnings after every statement.
nowarning (\\w) Don't show warnings after every statement.
For server side help, type 'help contents'
.fi
.RE
.PP
Each command has both a long and short form. The long form is not case sensitive; the short form is. The long form can be followed by an optional semicolon terminator, but the short form should not.
.PP
The use of short\-form commands within multi\-line
/* ... */
comments is not supported.
.TP 3n
\(bu
\fBhelp [\fR\fB\fIarg\fR\fR\fB]\fR,
\fB\\h [\fR\fB\fIarg\fR\fR\fB]\fR,
\fB\\? [\fR\fB\fIarg\fR\fR\fB]\fR,
\fB? [\fR\fB\fIarg\fR\fR\fB]\fR
.sp
Displays a help message listing the available
\fBmysql\fR
commands.
.sp
If you provide an argument to the
help
command,
\fBmysql\fR
uses it as a search string to access server\-side help from the contents of the Drizzle Reference Manual. For more information, see
the section called \(lq\fBMYSQL\fR SERVER\-SIDE HELP\(rq.
.TP 3n
\(bu
\fBcharset \fR\fB\fIcharset_name\fR\fR,
\fB\\C \fR\fB\fIcharset_name\fR\fR
.sp
The
charset
command changes the default character set and issues a
SET NAMES
statement. This enables the character set to remain synchronized on the client and server if
\fBmysql\fR
is run with auto\-reconnect enabled (which is not recommended), because the specified character set is used for reconnects.
.TP 3n
\(bu
\fBclear\fR,
\fB\\c\fR
.sp
Clears the current input. Use this if you change your mind about executing the statement that you are entering.
.TP 3n
\(bu
\fBconnect [\fR\fB\fIdb_name\fR\fR\fB \fR\fB\fIhost_name\fR\fR\fB]]\fR,
\fB\\r [\fR\fB\fIdb_name\fR\fR\fB \fR\fB\fIhost_name\fR\fR\fB]]\fR
.sp
Reconnects to the server. The optional database name and host name arguments may be given to specify the default database or the host where the server is running. If omitted, the current values are used.
.TP 3n
\(bu
\fBdelimiter \fR\fB\fIstr\fR\fR,
\fB\\d \fR\fB\fIstr\fR\fR
.sp
The
delimiter
command changes the string that
\fBmysql\fR
interprets as the separator between SQL statements. The default is the semicolon character (\(lq;\(rq).
.sp
The delimiter can be specified as an unquoted or quoted argument. Quoting can be done with either single quote (') or douple quote (") characters. To include a quote within a quoted string, either quote the string with the other quote character or escape the quote with a backslash (\(lq\\\(rq) character. Backslash should be avoided outside of quoted strings because it is the escape character for Drizzle. For an unquoted argument, the delmiter is read up to the first space or end of line. For a quoted argument, the delimiter is read up to the matching quote on the line.
.sp
When the delimiter recognized by
\fBmysql\fR
is set to something other than the default of
\(lq;\(rq, instances of that character are sent to the server without interpretation. However, the server itself still interprets
\(lq;\(rq
as a statement delimiter and processes statements accordingly. This behavior on the server side comes into play for multiple\-statement execution (see
Section\ 20.10.12, \(lqC API Support for Multiple Statement Execution\(rq), and for parsing the body of stored procedures and functions, triggers, and events (see
Section\ 18.1, \(lqDefining Stored Programs\(rq).
.TP 3n
\(bu
\fBedit\fR,
\fB\\e\fR
.sp
Edits the current input statement.
\fBmysql\fR
checks the values of the
EDITOR
and
VISUAL
environment variables to determine which editor to use. The default editor is
\fBvi\fR
if neither variable is set.
.sp
The
\fBedit\fR
command works only in Unix.
.TP 3n
\(bu
\fBego\fR,
\fB\\G\fR
.sp
Sends the current statement to the server to be executed and displays the result using vertical format.
.TP 3n
\(bu
\fBexit\fR,
\fB\\q\fR
.sp
Exits
\fBmysql\fR.
.TP 3n
\(bu
\fBgo\fR,
\fB\\g\fR
.sp
Sends the current statement to the server to be executed.
.TP 3n
\(bu
\fBnopager\fR,
\fB\\n\fR
.sp
Disables output paging. See the description for
\fBpager\fR.
.sp
The
\fBnopager\fR
command works only in Unix.
.TP 3n
\(bu
\fBnotee\fR,
\fB\\t\fR
.sp
Disables output copying to the tee file. See the description for
\fBtee\fR.
.TP 3n
\(bu
\fBnowarning\fR,
\fB\\w\fR
.sp
Enables display of warnings after each statement.
.TP 3n
\(bu
\fBpager [\fR\fB\fIcommand\fR\fR\fB]\fR,
\fB\\P [\fR\fB\fIcommand\fR\fR\fB]\fR
.sp
By using the
\fB\-\-pager\fR
option when you invoke
\fBmysql\fR, it is possible to browse or search query results in interactive mode with Unix programs such as
\fBless\fR,
\fBmore\fR, or any other similar program. If you specify no value for the option,
\fBmysql\fR
checks the value of the
PAGER
environment variable and sets the pager to that.
.sp
Output paging can be enabled interactively with the
\fBpager\fR
command and disabled with
\fBnopager\fR. The command takes an optional argument; if given, the paging program is set to that. With no argument, the pager is set to the pager that was set on the command line, or
stdout
if no pager was specified.
.sp
Output paging works only in Unix because it uses the
popen()
function, which does not exist on Windows. For Windows, the
\fBtee\fR
option can be used instead to save query output, although it is not as convenient as
\fBpager\fR
for browsing output in some situations.
.TP 3n
\(bu
\fBprint\fR,
\fB\\p\fR
.sp
Prints the current input statement without executing it.
.TP 3n
\(bu
\fBprompt [\fR\fB\fIstr\fR\fR\fB]\fR,
\fB\\R [\fR\fB\fIstr\fR\fR\fB]\fR
.sp
Reconfigures the
\fBmysql\fR
prompt to the given string. The special character sequences that can be used in the prompt are described later in this section.
.sp
If you specify the
prompt
command with no argument,
\fBmysql\fR
resets the prompt to the default of
mysql>.
.TP 3n
\(bu
\fBquit\fR,
\fB\\q\fR
.sp
Exits
\fBmysql\fR.
.TP 3n
\(bu
\fBrehash\fR,
\fB\\#\fR
.sp
Rebuilds the completion hash that enables database, table, and column name completion while you are entering statements. (See the description for the
\fB\-\-auto\-rehash\fR
option.)
.TP 3n
\(bu
\fBsource \fR\fB\fIfile_name\fR\fR,
\fB\\. \fR\fB\fIfile_name\fR\fR
.sp
Reads the named file and executes the statements contained therein. On Windows, you can specify path name separators as
/
or
\\\\.
.TP 3n
\(bu
\fBstatus\fR,
\fB\\s\fR
.sp
The
status
command provides some information about the connection and the server you are using. If you are running in
\fB\-\-safe\-updates\fR
mode,
status
also prints the values for the
\fBmysql\fR
variables that affect your queries.
.TP 3n
\(bu
\fBsystem \fR\fB\fIcommand\fR\fR,
\fB\\! \fR\fB\fIcommand\fR\fR
.sp
Executes the given command using your default command interpreter.
.sp
The
\fBsystem\fR
command works only in Unix.
.TP 3n
\(bu
\fBtee [\fR\fB\fIfile_name\fR\fR\fB]\fR,
\fB\\T [\fR\fB\fIfile_name\fR\fR\fB]\fR
.sp
By using the
\fB\-\-tee\fR
option when you invoke
\fBmysql\fR, you can log statements and their output. All the data displayed on the screen is appended into a given file. This can be very useful for debugging purposes also.
\fBmysql\fR
flushes results to the file after each statement, just before it prints its next prompt.
.sp
You can enable this feature interactively with the
\fBtee\fR
command. Without a parameter, the previous file is used. The
\fBtee\fR
file can be disabled with the
\fBnotee\fR
command. Executing
\fBtee\fR
again re\-enables logging.
.TP 3n
\(bu
\fBuse \fR\fB\fIdb_name\fR\fR,
\fB\\u \fR\fB\fIdb_name\fR\fR
.sp
Uses
\fIdb_name\fR
as the default database.
.TP 3n
\(bu
\fBwarnings\fR,
\fB\\W\fR
.sp
Enables display of warnings after each statement (if there are any).
.sp
.RE
.PP
Here are a few tips about the
\fBpager\fR
command:
.TP 3n
\(bu
You can use it to write to a file and the results go only to the file:
.sp
.RS 3n
.nf
mysql> \fBpager cat > /tmp/log.txt\fR
.fi
.RE
You can also pass any options for the program that you want to use as your pager:
.sp
.RS 3n
.nf
mysql> \fBpager less \-n \-i \-S\fR
.fi
.RE
.TP 3n
\(bu
In the preceding example, note the
\fB\-S\fR
option. You may find it very useful for browsing wide query results. Sometimes a very wide result set is difficult to read on the screen. The
\fB\-S\fR
option to
\fBless\fR
can make the result set much more readable because you can scroll it horizontally using the left\-arrow and right\-arrow keys. You can also use
\fB\-S\fR
interactively within
\fBless\fR
to switch the horizontal\-browse mode on and off. For more information, read the
\fBless\fR
manual page:
.sp
.RS 3n
.nf
shell> \fBman less\fR
.fi
.RE
.TP 3n
\(bu
The
\fB\-F\fR
and
\fB\-X\fR
options may be used with
\fBless\fR
to cause it to exit if output fits on one screen, which is convenient when no scrolling is necessary:
.sp
.RS 3n
.nf
mysql> \fBpager less \-n \-i \-S \-F \-X\fR
.fi
.RE
.TP 3n
\(bu
You can specify very complex pager commands for handling query output:
.sp
.RS 3n
.nf
mysql> \fBpager cat | tee /dr1/tmp/res.txt \\\fR
\fB| tee /dr2/tmp/res2.txt | less \-n \-i \-S\fR
.fi
.RE
In this example, the command would send query results to two files in two different directories on two different file systems mounted on
\fI/dr1\fR
and
\fI/dr2\fR, yet still display the results onscreen via
\fBless\fR.
.sp
.RE
.PP
You can also combine the
\fBtee\fR
and
\fBpager\fR
functions. Have a
\fBtee\fR
file enabled and
\fBpager\fR
set to
\fBless\fR, and you are able to browse the results using the
\fBless\fR
program and still have everything appended into a file the same time. The difference between the Unix
\fBtee\fR
used with the
\fBpager\fR
command and the
\fBmysql\fR
built\-in
\fBtee\fR
command is that the built\-in
\fBtee\fR
works even if you do not have the Unix
\fBtee\fR
available. The built\-in
\fBtee\fR
also logs everything that is printed on the screen, whereas the Unix
\fBtee\fR
used with
\fBpager\fR
does not log quite that much. Additionally,
\fBtee\fR
file logging can be turned on and off interactively from within
\fBmysql\fR. This is useful when you want to log some queries to a file, but not others.
.PP
The
\fBprompt\fR
command reconfigures the default
mysql>
prompt. The string for defining the prompt can contain the following special sequences.
.TS
allbox tab(:);
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l
l l.
T{
\fBOption\fR
T}:T{
\fBDescription\fR
T}
T{
\\o
T}:T{
The current month in numeric format
T}
T{
\\P
T}:T{
am/pm
T}
T{
\\p
T}:T{
The current TCP/IP port or socket file
T}
T{
\\R
T}:T{
The current time, in 24\-hour military time (0\-23)
T}
T{
\\r
T}:T{
The current time, standard 12\-hour time (1\-12)
T}
T{
\\S
T}:T{
Semicolon
T}
T{
\\s
T}:T{
Seconds of the current time
T}
T{
\\t
T}:T{
A tab character
T}
T{
\\U
T}:T{
Your full
\fIuser_name\fR@\fIhost_name\fR
account name
T}
T{
\\u
T}:T{
Your user name
T}
T{
\\c
T}:T{
A counter that increments for each statement you issue
T}
T{
\\v
T}:T{
The server version
T}
T{
\\w
T}:T{
The current day of the week in three\-letter format (Mon, Tue, \&...)
T}
T{
\\Y
T}:T{
The current year, four digits
T}
T{
\\y
T}:T{
The current year, two digits
T}
T{
\\_
T}:T{
A space
T}
T{
\\\
T}:T{
A space (a space follows the backslash)
T}
T{
\\'
T}:T{
Single quote
T}
T{
\\"
T}:T{
Double quote
T}
T{
\\\\
T}:T{
A literal \(lq\\\(rq backslash character
T}
T{
\\\fIx\fR
T}:T{
\fIx\fR, for any
\(lq\fIx\fR\(rq not listed
above
T}
T{
\\D
T}:T{
The full current date
T}
T{
\\d
T}:T{
The default database
T}
T{
\\h
T}:T{
The server host
T}
T{
\\l
T}:T{
The current delimiter
T}
T{
\\m
T}:T{
Minutes of the current time
T}
T{
\\n
T}:T{
A newline character
T}
T{
\\O
T}:T{
The current month in three\-letter format (Jan, Feb, \&...)
T}
.TE
.sp
.PP
You can set the prompt in several ways:
.TP 3n
\(bu
\fIUse an environment variable.\fR
You can set the
MYSQL_PS1
environment variable to a prompt string. For example:
.sp
.RS 3n
.nf
shell> \fBexport MYSQL_PS1="(\\u@\\h) [\\d]> "\fR
.fi
.RE
.TP 3n
\(bu
\fIUse a command\-line option.\fR
You can set the
\fB\-\-prompt\fR
option on the command line to
\fBmysql\fR. For example:
.sp
.RS 3n
.nf
shell> \fBmysql \-\-prompt="(\\u@\\h) [\\d]> "\fR
(user@host) [database]>
.fi
.RE
.TP 3n
\(bu
\fIUse an option file.\fR
You can set the
prompt
option in the
[mysql]
group of any Drizzle option file, such as
\fI/etc/my.cnf\fR
or the
\fI.my.cnf\fR
file in your home directory. For example:
.sp
.RS 3n
.nf
[mysql]
prompt=(\\\\u@\\\\h) [\\\\d]>\\\\_
.fi
.RE
In this example, note that the backslashes are doubled. If you set the prompt using the
prompt
option in an option file, it is advisable to double the backslashes when using the special prompt options. There is some overlap in the set of allowable prompt options and the set of special escape sequences that are recognized in option files. (These sequences are listed in
Section\ 4.2.3.2, \(lqUsing Option Files\(rq.) The overlap may cause you problems if you use single backslashes. For example,
\\s
is interpreted as a space rather than as the current seconds value. The following example shows how to define a prompt within an option file to include the current time in
HH:MM:SS>
format:
.sp
.RS 3n
.nf
[mysql]
prompt="\\\\r:\\\\m:\\\\s> "
.fi
.RE
.TP 3n
\(bu
\fISet the prompt interactively.\fR
You can change your prompt interactively by using the
prompt
(or
\\R) command. For example:
.sp
.RS 3n
.nf
mysql> \fBprompt (\\u@\\h) [\\d]>\\_\fR
PROMPT set to '(\\u@\\h) [\\d]>\\_'
(\fIuser\fR@\fIhost\fR) [\fIdatabase\fR]>
(\fIuser\fR@\fIhost\fR) [\fIdatabase\fR]> prompt
Returning to default PROMPT of mysql>
mysql>
.fi
.RE
.SH "\fBMYSQL\fR SERVER\-SIDE HELP"
.sp
.RS 3n
.nf
mysql> \fBhelp \fR\fB\fIsearch_string\fR\fR
.fi
.RE
.PP
If you provide an argument to the
help
command,
\fBmysql\fR
uses it as a search string to access server\-side help from the contents of the Drizzle Reference Manual. The proper operation of this command requires that the help tables in the
mysql
database be initialized with help topic information (see
Section\ 5.1.8, \(lqServer\-Side Help\(rq).
.PP
If there is no match for the search string, the search fails:
.sp
.RS 3n
.nf
mysql> \fBhelp me\fR
Nothing found
Please try to run 'help contents' for a list of all accessible topics
.fi
.RE
.PP
Use
\fBhelp contents\fR
to see a list of the help categories:
.sp
.RS 3n
.nf
mysql> \fBhelp contents\fR
You asked for help about help category: "Contents"
For more information, type 'help <item>', where <item> is one of the
following categories:
Account Management
Administration
Data Definition
Data Manipulation
Data Types
Functions
Functions and Modifiers for Use with GROUP BY
Geographic Features
Language Structure
Plugins
Storage Engines
Stored Routines
Table Maintenance
Transactions
Triggers
.fi
.RE
.PP
If the search string matches multiple items,
\fBmysql\fR
shows a list of matching topics:
.sp
.RS 3n
.nf
mysql> \fBhelp logs\fR
Many help items for your request exist.
To make a more specific request, please type 'help <item>',
where <item> is one of the following topics:
SHOW
SHOW BINARY LOGS
SHOW ENGINE
SHOW LOGS
.fi
.RE
.PP
Use a topic as the search string to see the help entry for that topic:
.sp
.RS 3n
.nf
mysql> \fBhelp show binary logs\fR
Name: 'SHOW BINARY LOGS'
Description:
Syntax:
SHOW BINARY LOGS
SHOW MASTER LOGS
Lists the binary log files on the server. This statement is used as
part of the procedure described in [purge\-binary\-logs], that shows how
to determine which logs can be purged.
mysql> SHOW BINARY LOGS;
+\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-+\-\-\-\-\-\-\-\-\-\-\-+
| Log_name | File_size |
+\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-+\-\-\-\-\-\-\-\-\-\-\-+
| binlog.000015 | 724935 |
| binlog.000016 | 733481 |
+\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-+\-\-\-\-\-\-\-\-\-\-\-+
.fi
.RE
.SH "EXECUTING SQL STATEMENTS FROM A TEXT FILE"
.PP
The
\fBmysql\fR
client typically is used interactively, like this:
.sp
.RS 3n
.nf
shell> \fBmysql \fR\fB\fIdb_name\fR\fR
.fi
.RE
.PP
However, it is also possible to put your SQL statements in a file and then tell
\fBmysql\fR
to read its input from that file. To do so, create a text file
\fItext_file\fR
that contains the statements you wish to execute. Then invoke
\fBmysql\fR
as shown here:
.sp
.RS 3n
.nf
shell> \fBmysql \fR\fB\fIdb_name\fR\fR\fB < \fR\fB\fItext_file\fR\fR
.fi
.RE
.PP
If you place a
USE \fIdb_name\fR
statement as the first statement in the file, it is unnecessary to specify the database name on the command line:
.sp
.RS 3n
.nf
shell> \fBmysql < text_file\fR
.fi
.RE
.PP
If you are already running
\fBmysql\fR, you can execute an SQL script file using the
source
command or
\\.
command:
.sp
.RS 3n
.nf
mysql> \fBsource \fR\fB\fIfile_name\fR\fR
mysql> \fB\\. \fR\fB\fIfile_name\fR\fR
.fi
.RE
.PP
Sometimes you may want your script to display progress information to the user. For this you can insert statements like this:
.sp
.RS 3n
.nf
SELECT '<info_to_display>' AS ' ';
.fi
.RE
.PP
The statement shown outputs
<info_to_display>.
.PP
As of Drizzle 6.0.4,
\fBmysql\fR
ignores Unicode byte order mark (BOM) characters at the beginning of input files. Previously, it read them and sent them to the server, resulting in a syntax error. Presence of a BOM does not cause
\fBmysql\fR
to change its default character set. To do that, invoke
\fBmysql\fR
with an option such as
\fB\-\-default\-character\-set=utf8\fR.
.PP
For more information about batch mode, see
Section\ 3.5, \(lqUsing \fBmysql\fR in Batch Mode\(rq.
.SH "\fBMYSQL\fR TIPS"
.PP
This section describes some techniques that can help you use
\fBmysql\fR
more effectively.
.SS "Displaying Query Results Vertically"
.PP
Some query results are much more readable when displayed vertically, instead of in the usual horizontal table format. Queries can be displayed vertically by terminating the query with \\G instead of a semicolon. For example, longer text values that include newlines often are much easier to read with vertical output:
.sp
.RS 3n
.nf
mysql> \fBSELECT * FROM mails WHERE LENGTH(txt) < 300 LIMIT 300,1\\G\fR
*************************** 1. row ***************************
msg_nro: 3068
date: 2000\-03\-01 23:29:50
time_zone: +0200
mail_from: Monty
reply: monty@no.spam.com
mail_to: "Thimble Smith" <tim@no.spam.com>
sbj: UTF\-8
txt: >>>>> "Thimble" == Thimble Smith writes:
Thimble> Hi. I think this is a good idea. Is anyone familiar
Thimble> with UTF\-8 or Unicode? Otherwise, I'll put this on my
Thimble> TODO list and see what happens.
Yes, please do that.
Regards,
Monty
file: inbox\-jani\-1
hash: 190402944
1 row in set (0.09 sec)
.fi
.RE
.\" end of SS subsection "Displaying Query Results Vertically"
.SS "Using the \-\-safe\-updates Option"
.PP
For beginners, a useful startup option is
\fB\-\-safe\-updates\fR
(or
\fB\-\-i\-am\-a\-dummy\fR, which has the same effect). It is helpful for cases when you might have issued a
DELETE FROM \fItbl_name\fR
statement but forgotten the
WHERE
clause. Normally, such a statement deletes all rows from the table. With
\fB\-\-safe\-updates\fR, you can delete rows only by specifying the key values that identify them. This helps prevent accidents.
.PP
When you use the
\fB\-\-safe\-updates\fR
option,
\fBmysql\fR
issues the following statement when it connects to the Drizzle server:
.sp
.RS 3n
.nf
SET sql_safe_updates=1, sql_select_limit=1000, sql_max_join_size=1000000;
.fi
.RE
.PP
See
Section\ 5.1.4, \(lqSession System Variables\(rq.
.PP
The
SET
statement has the following effects:
.TP 3n
\(bu
You are not allowed to execute an
UPDATE
or
DELETE
statement unless you specify a key constraint in the
WHERE
clause or provide a
LIMIT
clause (or both). For example:
.sp
.RS 3n
.nf
UPDATE \fItbl_name\fR SET \fInot_key_column\fR=\fIval\fR WHERE \fIkey_column\fR=\fIval\fR;
UPDATE \fItbl_name\fR SET \fInot_key_column\fR=\fIval\fR LIMIT 1;
.fi
.RE
.TP 3n
\(bu
The server limits all large
SELECT
results to 1,000 rows unless the statement includes a
LIMIT
clause.
.TP 3n
\(bu
The server aborts multiple\-table
SELECT
statements that probably need to examine more than 1,000,000 row combinations.
.sp
.RE
.PP
To specify limits different from 1,000 and 1,000,000, you can override the defaults by using the
\fB\-\-select_limit\fR
and
\fB\-\-max_join_size\fR
options:
.sp
.RS 3n
.nf
shell> \fBmysql \-\-safe\-updates \-\-select_limit=500 \-\-max_join_size=10000\fR
.fi
.RE
.\" end of SS subsection "Using the \-\-safe\-updates Option"
.SS "Disabling mysql Auto\-Reconnect"
.PP
If the
\fBmysql\fR
client loses its connection to the server while sending a statement, it immediately and automatically tries to reconnect once to the server and send the statement again. However, even if
\fBmysql\fR
succeeds in reconnecting, your first connection has ended and all your previous session objects and settings are lost: temporary tables, the autocommit mode, and user\-defined and session variables. Also, any current transaction rolls back. This behavior may be dangerous for you, as in the following example where the server was shut down and restarted between the first and second statements without you knowing it:
.sp
.RS 3n
.nf
mysql> \fBSET @a=1;\fR
Query OK, 0 rows affected (0.05 sec)
mysql> \fBINSERT INTO t VALUES(@a);\fR
ERROR 2006: Drizzle server has gone away
No connection. Trying to reconnect...
Connection id: 1
Current database: test
Query OK, 1 row affected (1.30 sec)
mysql> \fBSELECT * FROM t;\fR
+\-\-\-\-\-\-+
| a |
+\-\-\-\-\-\-+
| NULL |
+\-\-\-\-\-\-+
1 row in set (0.05 sec)
.fi
.RE
.PP
The
@a
user variable has been lost with the connection, and after the reconnection it is undefined. If it is important to have
\fBmysql\fR
terminate with an error if the connection has been lost, you can start the
\fBmysql\fR
client with the
\fB\-\-skip\-reconnect\fR
option.
.PP
For more information about auto\-reconnect and its effect on state information when a reconnection occurs, see
Section\ 20.10.11, \(lqControlling Automatic Reconnection Behavior\(rq.
.\" end of SS subsection "Disabling mysql Auto\-Reconnect"
.SH "COPYRIGHT"
.PP
Copyright 2007\-2008 MySQL AB, 2009 Sun Microsystems, Inc.
.PP
This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.
.PP
This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
.PP
You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110\-1301 USA or see http://www.gnu.org/licenses/.
.SH "REFERENCES"
.TP 3
1.\ Bug#25946
\%http://bugs.mysql.com/25946
.SH "SEE ALSO"
For more information, please refer to the Drizzle Reference Manual,
which may already be installed locally and which is also available
online at http://dev.mysql.com/doc/.
.SH AUTHOR
Sun Microsystems, Inc. (http://www.mysql.com/).
|