I386LINUX/util/I386LINUX/doc/postgresql/html/sql-delete.html

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  90 ><H1
  91 ><A
  92 NAME="SQL-DELETE"
  93 ></A
  94 >DELETE</H1
  95 ><DIV
  96 CLASS="REFNAMEDIV"
  97 ><A
  98 NAME="AEN39301"
  99 ></A
 100 ><H2
 101 >Name</H2
 102 >DELETE&nbsp;--&nbsp;delete rows of a table</DIV
 103 ><A
 104 NAME="AEN39304"
 105 ></A
 106 ><DIV
 107 CLASS="REFSYNOPSISDIV"
 108 ><A
 109 NAME="AEN39306"
 110 ></A
 111 ><H2
 112 >Synopsis</H2
 113 ><PRE
 114 CLASS="SYNOPSIS"
 115 >DELETE FROM [ ONLY ] <VAR
 116 CLASS="REPLACEABLE"
 117 >table</VAR
 118 > [ WHERE <VAR
 119 CLASS="REPLACEABLE"
 120 >condition</VAR
 121 > ]</PRE
 122 ></DIV
 123 ><DIV
 124 CLASS="REFSECT1"
 125 ><A
 126 NAME="AEN39310"
 127 ></A
 128 ><H2
 129 >Description</H2
 130 ><P
 131 >   <TT
 132 CLASS="COMMAND"
 133 >DELETE</TT
 134 > deletes rows that satisfy the
 135    <TT
 136 CLASS="LITERAL"
 137 >WHERE</TT
 138 > clause from the specified table.  If the
 139    <TT
 140 CLASS="LITERAL"
 141 >WHERE</TT
 142 > clause is absent, the effect is to delete
 143    all rows in the table.  The result is a valid, but empty table.
 144   </P
 145 ><DIV
 146 CLASS="TIP"
 147 ><BLOCKQUOTE
 148 CLASS="TIP"
 149 ><P
 150 ><B
 151 >Tip: </B
 152 >     <A
 153 HREF="sql-truncate.html"
 154 ><I
 155 >TRUNCATE</I
 156 ></A
 157 > is a
 158      <SPAN
 159 CLASS="PRODUCTNAME"
 160 >PostgreSQL</SPAN
 161 > extension which provides a
 162      faster mechanism to remove all rows from a table.
 163     </P
 164 ></BLOCKQUOTE
 165 ></DIV
 166 ><P
 167 >   By default, <TT
 168 CLASS="COMMAND"
 169 >DELETE</TT
 170 > will delete rows in the
 171    specified table and all its subtables. If you wish to only delete
 172    from the specific table mentioned, you must use the
 173    <TT
 174 CLASS="LITERAL"
 175 >ONLY</TT
 176 > clause.
 177   </P
 178 ><P
 179 >   You must have the <TT
 180 CLASS="LITERAL"
 181 >DELETE</TT
 182 > privilege on the table
 183    to delete from it, as well as the <TT
 184 CLASS="LITERAL"
 185 >SELECT</TT
 186 >
 187    privilege for any table whose values are read in the <VAR
 188 CLASS="REPLACEABLE"
 189 >condition</VAR
 190 >.
 191   </P
 192 ></DIV
 193 ><DIV
 194 CLASS="REFSECT1"
 195 ><A
 196 NAME="AEN39327"
 197 ></A
 198 ><H2
 199 >Parameters</H2
 200 ><P
 201 ></P
 202 ><DIV
 203 CLASS="VARIABLELIST"
 204 ><DL
 205 ><DT
 206 ><VAR
 207 CLASS="REPLACEABLE"
 208 >table</VAR
 209 ></DT
 210 ><DD
 211 ><P
 212 >      The name (optionally schema-qualified) of an existing table.
 213      </P
 214 ></DD
 215 ><DT
 216 ><VAR
 217 CLASS="REPLACEABLE"
 218 >condition</VAR
 219 ></DT
 220 ><DD
 221 ><P
 222 >      A value expression that returns a value of type
 223       <TT
 224 CLASS="TYPE"
 225 >boolean</TT
 226 > that determines the rows which are to be
 227       deleted.
 228      </P
 229 ></DD
 230 ></DL
 231 ></DIV
 232 ></DIV
 233 ><DIV
 234 CLASS="REFSECT1"
 235 ><A
 236 NAME="AEN39341"
 237 ></A
 238 ><H2
 239 >Outputs</H2
 240 ><P
 241 >   On successful completion, a <TT
 242 CLASS="COMMAND"
 243 >DELETE</TT
 244 > command returns a command
 245    tag of the form
 246 </P><PRE
 247 CLASS="SCREEN"
 248 >DELETE <VAR
 249 CLASS="REPLACEABLE"
 250 >count</VAR
 251 ></PRE
 252 ><P>
 253    The <VAR
 254 CLASS="REPLACEABLE"
 255 >count</VAR
 256 > is the number
 257    of rows deleted.  If <VAR
 258 CLASS="REPLACEABLE"
 259 >count</VAR
 260 > is
 261    0, no rows matched the <VAR
 262 CLASS="REPLACEABLE"
 263 >condition</VAR
 264 > (this is not considered
 265    an error).
 266   </P
 267 ></DIV
 268 ><DIV
 269 CLASS="REFSECT1"
 270 ><A
 271 NAME="AEN39350"
 272 ></A
 273 ><H2
 274 >Examples</H2
 275 ><P
 276 >   Delete all films but musicals:
 277 </P><PRE
 278 CLASS="PROGRAMLISTING"
 279 >DELETE FROM films WHERE kind &lt;&gt; 'Musical';</PRE
 280 ><P>
 281   </P
 282 ><P
 283 >   Clear the table <TT
 284 CLASS="LITERAL"
 285 >films</TT
 286 >:
 287 </P><PRE
 288 CLASS="PROGRAMLISTING"
 289 >DELETE FROM films;</PRE
 290 ><P>
 291   </P
 292 ></DIV
 293 ><DIV
 294 CLASS="REFSECT1"
 295 ><A
 296 NAME="AEN39357"
 297 ></A
 298 ><H2
 299 >Compatibility</H2
 300 ><P
 301 >   This command conforms to the SQL standard.
 302   </P
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