I386LINUX/util/I386LINUX/doc/postgresql/html/libpq-envars.html

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  97 ><A
  98 NAME="LIBPQ-ENVARS"
  99 >27.10. Environment Variables</A
 100 ></H1
 101 ><A
 102 NAME="AEN21725"
 103 ></A
 104 ><P
 105 >The following environment variables can be used to select default
 106 connection parameter values, which will be used by
 107 <CODE
 108 CLASS="FUNCTION"
 109 >PQconnectdb</CODE
 110 >, <CODE
 111 CLASS="FUNCTION"
 112 >PQsetdbLogin</CODE
 113 > and
 114 <CODE
 115 CLASS="FUNCTION"
 116 >PQsetdb</CODE
 117 > if no value is directly specified by the calling
 118 code.  These are useful to avoid hard-coding database connection
 119 information into simple client applications, for example.
 120
 121 <P
 122 ></P
 123 ></P><UL
 124 ><LI
 125 ><P
 126 ><A
 127 NAME="AEN21734"
 128 ></A
 129 >
 130 <TT
 131 CLASS="ENVAR"
 132 >PGHOST</TT
 133 > sets the database server name.
 134 If this begins with a slash, it specifies Unix-domain communication
 135 rather than TCP/IP communication; the value is the name of the
 136 directory in which the socket file is stored (default <TT
 137 CLASS="FILENAME"
 138 >/tmp</TT
 139 >).</P
 140 ></LI
 141 ><LI
 142 ><P
 143 ><A
 144 NAME="AEN21741"
 145 ></A
 146 >
 147 <TT
 148 CLASS="ENVAR"
 149 >PGHOSTADDR</TT
 150 > specifies the numeric IP address of the database
 151 server.  This can be set instead of <TT
 152 CLASS="ENVAR"
 153 >PGHOST</TT
 154 > to avoid DNS
 155 lookup overhead. See the documentation of
 156 these parameters, under <CODE
 157 CLASS="FUNCTION"
 158 >PQconnectdb</CODE
 159 > above, for details
 160 on their interaction.</P
 161 ></LI
 162 ><LI
 163 ><P
 164 ><A
 165 NAME="AEN21749"
 166 ></A
 167 >
 168 <TT
 169 CLASS="ENVAR"
 170 >PGPORT</TT
 171 > sets the TCP port number or Unix-domain
 172 socket file extension for communicating with the
 173 <SPAN
 174 CLASS="PRODUCTNAME"
 175 >PostgreSQL</SPAN
 176 > server.</P
 177 ></LI
 178 ><LI
 179 ><P
 180 ><A
 181 NAME="AEN21756"
 182 ></A
 183 >
 184 <TT
 185 CLASS="ENVAR"
 186 >PGDATABASE</TT
 187 >  sets the
 188 <SPAN
 189 CLASS="PRODUCTNAME"
 190 >PostgreSQL</SPAN
 191 > database name.</P
 192 ></LI
 193 ><LI
 194 ><P
 195 ><A
 196 NAME="AEN21763"
 197 ></A
 198 >
 199 <TT
 200 CLASS="ENVAR"
 201 >PGUSER</TT
 202 >
 203 sets the user name used to connect to the database.</P
 204 ></LI
 205 ><LI
 206 ><P
 207 ><A
 208 NAME="AEN21769"
 209 ></A
 210 >
 211 <TT
 212 CLASS="ENVAR"
 213 >PGPASSWORD</TT
 214 >
 215 sets the password used if the server demands password
 216 authentication.  This environment variable is deprecated for security
 217 reasons; consider migrating to use the <TT
 218 CLASS="FILENAME"
 219 >$HOME/.pgpass</TT
 220 >
 221 file (see <A
 222 HREF="libpq-pgpass.html"
 223 >Section 27.11</A
 224 >).</P
 225 ></LI
 226 ><LI
 227 ><P
 228 ><A
 229 NAME="AEN21777"
 230 ></A
 231 >
 232 <TT
 233 CLASS="ENVAR"
 234 >PGSERVICE</TT
 235 >
 236 sets the service name to be looked up in <TT
 237 CLASS="FILENAME"
 238 >pg_service.conf</TT
 239 >.
 240 This offers a shorthand way of setting all the parameters.</P
 241 ></LI
 242 ><LI
 243 ><P
 244 ><A
 245 NAME="AEN21784"
 246 ></A
 247 >
 248 <TT
 249 CLASS="ENVAR"
 250 >PGREALM</TT
 251 > sets the Kerberos realm to  use  with
 252 <SPAN
 253 CLASS="PRODUCTNAME"
 254 >PostgreSQL</SPAN
 255 >, if  it is different from the local realm.
 256 If <TT
 257 CLASS="ENVAR"
 258 >PGREALM</TT
 259 > is set, <SPAN
 260 CLASS="APPLICATION"
 261 >libpq</SPAN
 262 >
 263 applications  will  attempt authentication  with  servers for this realm and use
 264 separate ticket files to avoid conflicts with  local
 265 ticket  files.   This  environment  variable is only
 266 used if Kerberos authentication is selected by the server.</P
 267 ></LI
 268 ><LI
 269 ><P
 270 ><A
 271 NAME="AEN21793"
 272 ></A
 273 >
 274 <TT
 275 CLASS="ENVAR"
 276 >PGOPTIONS</TT
 277 > sets additional run-time  options  for
 278 the <SPAN
 279 CLASS="PRODUCTNAME"
 280 >PostgreSQL</SPAN
 281 > server.</P
 282 ></LI
 283 ><LI
 284 ><P
 285 ><A
 286 NAME="AEN21800"
 287 ></A
 288 >
 289 <TT
 290 CLASS="ENVAR"
 291 >PGSSLMODE</TT
 292 > determines whether and with what priority an
 293 <ACRONYM
 294 CLASS="ACRONYM"
 295 >SSL</ACRONYM
 296 > connection will be negotiated with the server. There are
 297 four modes: <TT
 298 CLASS="LITERAL"
 299 >disable</TT
 300 > will attempt only an unencrypted
 301 <ACRONYM
 302 CLASS="ACRONYM"
 303 >SSL</ACRONYM
 304 > connection; <TT
 305 CLASS="LITERAL"
 306 >allow</TT
 307 > will negotiate,
 308 trying first a non-<ACRONYM
 309 CLASS="ACRONYM"
 310 >SSL</ACRONYM
 311 > connection, then if that fails,
 312 trying an <ACRONYM
 313 CLASS="ACRONYM"
 314 >SSL</ACRONYM
 315 > connection; <TT
 316 CLASS="LITERAL"
 317 >prefer</TT
 318 >
 319 (the default) will negotiate, trying first an <ACRONYM
 320 CLASS="ACRONYM"
 321 >SSL</ACRONYM
 322 >
 323 connection, then if that fails, trying a regular non-<ACRONYM
 324 CLASS="ACRONYM"
 325 >SSL</ACRONYM
 326 >
 327 connection; <TT
 328 CLASS="LITERAL"
 329 >require</TT
 330 > will try only an <ACRONYM
 331 CLASS="ACRONYM"
 332 >SSL</ACRONYM
 333 >
 334 connection. If <SPAN
 335 CLASS="PRODUCTNAME"
 336 >PostgreSQL</SPAN
 337 > is compiled without SSL support,
 338 using option <TT
 339 CLASS="LITERAL"
 340 >require</TT
 341 > will cause an error, and options
 342 <TT
 343 CLASS="LITERAL"
 344 >allow</TT
 345 > and <TT
 346 CLASS="LITERAL"
 347 >prefer</TT
 348 > will be tolerated but
 349 <SPAN
 350 CLASS="APPLICATION"
 351 >libpq</SPAN
 352 > will be unable to negotiate an <ACRONYM
 353 CLASS="ACRONYM"
 354 >SSL</ACRONYM
 355 >
 356 connection.</P
 357 ></LI
 358 ><LI
 359 ><P
 360 ><A
 361 NAME="AEN21823"
 362 ></A
 363 >
 364 <TT
 365 CLASS="ENVAR"
 366 >PGREQUIRESSL</TT
 367 > sets whether or not the connection must be
 368 made over <ACRONYM
 369 CLASS="ACRONYM"
 370 >SSL</ACRONYM
 371 >. If set to
 372 <SPAN
 373 CLASS="QUOTE"
 374 >"1"</SPAN
 375 >, <SPAN
 376 CLASS="APPLICATION"
 377 >libpq</SPAN
 378 >
 379 will refuse to connect if the server does not accept
 380 an <ACRONYM
 381 CLASS="ACRONYM"
 382 >SSL</ACRONYM
 383 > connection (equivalent to <TT
 384 CLASS="LITERAL"
 385 >sslmode</TT
 386 >
 387 <TT
 388 CLASS="LITERAL"
 389 >prefer</TT
 390 >).
 391 This option is deprecated in favor of the <TT
 392 CLASS="LITERAL"
 393 >sslmode</TT
 394 >
 395 setting, and is only available if
 396 <SPAN
 397 CLASS="PRODUCTNAME"
 398 >PostgreSQL</SPAN
 399 > is compiled with SSL support.</P
 400 ></LI
 401 ><LI
 402 ><P
 403 ><A
 404 NAME="AEN21837"
 405 ></A
 406 >
 407 <TT
 408 CLASS="ENVAR"
 409 >PGCONNECT_TIMEOUT</TT
 410 > sets the maximum number of seconds
 411 that <SPAN
 412 CLASS="APPLICATION"
 413 >libpq</SPAN
 414 > will wait when attempting to
 415 connect to the <SPAN
 416 CLASS="PRODUCTNAME"
 417 >PostgreSQL</SPAN
 418 > server.  If unset
 419 or set to zero, <SPAN
 420 CLASS="APPLICATION"
 421 >libpq</SPAN
 422 > will wait indefinitely.
 423 It is not recommended to set the timeout to less than 2 seconds.</P
 424 ></LI
 425 ></UL
 426 ><P></P
 427 ><P
 428 >The following environment variables can be used to specify default
 429 behavior for each <SPAN
 430 CLASS="PRODUCTNAME"
 431 >PostgreSQL</SPAN
 432 > session.
 433 (See also the <TT
 434 CLASS="COMMAND"
 435 >ALTER USER</TT
 436 > and <TT
 437 CLASS="COMMAND"
 438 >ALTER DATABASE</TT
 439 >
 440 commands for ways to set default behavior on a per-user or per-database
 441 basis.)
 442
 443 <P
 444 ></P
 445 ></P><UL
 446 ><LI
 447 ><P
 448 ><A
 449 NAME="AEN21851"
 450 ></A
 451 >
 452 <TT
 453 CLASS="ENVAR"
 454 >PGDATESTYLE</TT
 455 >
 456 sets the default style of date/time representation.
 457 (Equivalent to <TT
 458 CLASS="LITERAL"
 459 >SET datestyle TO ...</TT
 460 >.)</P
 461 ></LI
 462 ><LI
 463 ><P
 464 ><A
 465 NAME="AEN21858"
 466 ></A
 467 >
 468 <TT
 469 CLASS="ENVAR"
 470 >PGTZ</TT
 471 >
 472 sets the default time zone.
 473 (Equivalent to <TT
 474 CLASS="LITERAL"
 475 >SET timezone TO ...</TT
 476 >.)</P
 477 ></LI
 478 ><LI
 479 ><P
 480 ><A
 481 NAME="AEN21865"
 482 ></A
 483 >
 484 <TT
 485 CLASS="ENVAR"
 486 >PGCLIENTENCODING</TT
 487 >
 488 sets the default client character set encoding.
 489 (Equivalent to <TT
 490 CLASS="LITERAL"
 491 >SET client_encoding TO ...</TT
 492 >.)</P
 493 ></LI
 494 ><LI
 495 ><P
 496 ><A
 497 NAME="AEN21872"
 498 ></A
 499 >
 500 <TT
 501 CLASS="ENVAR"
 502 >PGGEQO</TT
 503 >
 504 sets the default mode for the genetic query optimizer.
 505 (Equivalent to <TT
 506 CLASS="LITERAL"
 507 >SET geqo TO ...</TT
 508 >.)</P
 509 ></LI
 510 ></UL
 511 ><P>
 512
 513 Refer to the <ACRONYM
 514 CLASS="ACRONYM"
 515 >SQL</ACRONYM
 516 > command <TT
 517 CLASS="COMMAND"
 518 >SET</TT
 519 >
 520 for information on correct values for these environment variables.</P
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