Updates to the documentation. Changed version number to 2.4.0-beta1 (CVS 417)
FossilOrigin-Name: 36a8fe0ad0ee2a67afafc04125dcc085ec1b5a13
This commit is contained in:
drh
parent
4ff6dfa7de
commit
ef2daf547d
24
manifest
24
manifest
@ -1,9 +1,9 @@
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C More\sbugs\sfixed\sfor\sviews.\s(CVS\s416)
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D 2002-03-03T23:06:01
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C Updates\sto\sthe\sdocumentation.\s\sChanged\sversion\snumber\sto\s2.4.0-beta1\s(CVS\s417)
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D 2002-03-04T02:26:16
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F Makefile.in 50f1b3351df109b5774771350d8c1b8d3640130d
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F Makefile.template 89e373b2dad0321df00400fa968dc14b61a03296
|
||||
F README a4c0ba11354ef6ba0776b400d057c59da47a4cc0
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F VERSION 80c0f75cf7de338f1c6c31c07f5576d21f764431
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F VERSION bb1eea85a80e8034130db85d6c0857abe42c9460
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F aclocal.m4 11faa843caa38fd451bc6aeb43e248d1723a269d
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F config.guess f38b1e93d1e0fa6f5a6913e9e7b12774b9232588
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F config.log 6a73d03433669b10a3f0c221198c3f26b9413914
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@ -21,10 +21,10 @@ F sqlite.1 2e2bb0529ef468ade9e4322bd609d0695fb9ded9
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F src/TODO af7f3cab0228e34149cf98e073aa83d45878e7e6
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F src/btree.c d25ea795a0f7017bc2099c437e6cc01d4c31b22d
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F src/btree.h 8abeabfe6e0b1a990b64fa457592a6482f6674f3
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F src/build.c 5b91d41cbeed1da348a43a8af3eb5a7ce5812673
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F src/build.c e11b0daa79ba894c7476c33372b1dc42b13471e6
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F src/delete.c 577da499162291c1855f0b304b211bffcf9da945
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F src/expr.c e12ca550536c0bae7a3acef49dfa3068fe5f0900
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F src/func.c 5b4d9707b0c8f463824c1f04547b524cba24bf7b
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F src/func.c 87516e7dc37190c24af77593931a5d09d797520a
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F src/hash.c cc259475e358baaf299b00a2c7370f2b03dda892
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F src/hash.h dca065dda89d4575f3176e75e9a3dc0f4b4fb8b9
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F src/insert.c 42bfd145efd428d7e5f200dd49ea0b816fc30d79
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@ -111,23 +111,23 @@ F tool/report1.txt 9eae07f26a8fc53889b45fc833a66a33daa22816
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F www/arch.fig d5f9752a4dbf242e9cfffffd3f5762b6c63b3bcf
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F www/arch.png 82ef36db1143828a7abc88b1e308a5f55d4336f4
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F www/arch.tcl 72a0c80e9054cc7025a50928d28d9c75c02c2b8b
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F www/c_interface.tcl 63efc40f09e2f0d8fea43d174103248b160fdf0e
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F www/changes.tcl 18df8bc8dbcefbfd9538ce476d4fcbc193ac3352
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F www/c_interface.tcl 567cda531aac9d68a61ef02e26c6b202bd856db2
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F www/changes.tcl cdd351b0f358bc23ca6243f3ca52c35ca1bede26
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F www/conflict.tcl 81dd21f9a679e60aae049e9dd8ab53d59570cda2
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F www/crosscompile.tcl 3622ebbe518927a3854a12de51344673eb2dd060
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F www/download.tcl a6d75b8b117cd33dcb090bef7e80d7556d28ebe0
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F www/dynload.tcl 02eb8273aa78cfa9070dd4501dca937fb22b466c
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F www/faq.tcl c6d1d6d69a9083734ee73d1b5ee4253ae8f10074
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F www/formatchng.tcl 2d9a35c787823b48d72a5c64bb5414a43e26d5ad
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F www/formatchng.tcl 5cffc0ebd00b3085c976a527eeeef70db4ccc7a7
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F www/index.tcl eacd99bcc3132d6e6b74a51422d415cc0bf7bfdf
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F www/lang.tcl 01e47b43cb81cd24bd2918a2e1bd31a959097279
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F www/lang.tcl db13f9a9c5ce7a400fa7ae021cd99dc6b05fd74a
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F www/mingw.tcl f1c7c0a7f53387dd9bb4f8c7e8571b7561510ebc
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F www/opcode.tcl bdec8ef9f100dbd87bbef8976c54b88e43fd8ccc
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F www/speed.tcl 83457b2bf6bb430900bd48ca3dd98264d9a916a5
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F www/sqlite.tcl 8b5884354cb615049aed83039f8dfe1552a44279
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F www/tclsqlite.tcl 829b393d1ab187fd7a5e978631b3429318885c49
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F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218
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P 6121e5ab9328c90c64d40ade3de73ad11d4aaf4e
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R 83a8a52daf3c29d4bf2f935e98a598c9
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P 813077623087ffc6cd506f57cf6d1e3d9239f806
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R fe676fb38cbe5a2068c89e56308a155d
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U drh
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Z 8a99e2c5584a6641ebfdb027f72777c2
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Z 9a81a81e1e363e5bb6c841e14ddef308
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@ -1 +1 @@
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813077623087ffc6cd506f57cf6d1e3d9239f806
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36a8fe0ad0ee2a67afafc04125dcc085ec1b5a13
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17
src/build.c
17
src/build.c
@ -25,7 +25,7 @@
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** ROLLBACK
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** PRAGMA
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**
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** $Id: build.c,v 1.83 2002/03/03 23:06:01 drh Exp $
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** $Id: build.c,v 1.84 2002/03/04 02:26:16 drh Exp $
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*/
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#include "sqliteInt.h"
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#include <ctype.h>
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@ -1508,20 +1508,9 @@ void sqliteCopy(
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zTab = sqliteTableNameFromToken(pTableName);
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if( sqlite_malloc_failed || zTab==0 ) goto copy_cleanup;
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pTab = sqliteFindTable(db, zTab);
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pTab = sqliteTableNameToTable(pParse, zTab);
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sqliteFree(zTab);
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if( pTab==0 ){
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sqliteSetNString(&pParse->zErrMsg, "no such table: ", 0,
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pTableName->z, pTableName->n, 0);
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pParse->nErr++;
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goto copy_cleanup;
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}
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if( pTab->readOnly ){
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sqliteSetString(&pParse->zErrMsg, "table ", pTab->zName,
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" may not be modified", 0);
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pParse->nErr++;
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goto copy_cleanup;
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}
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if( pTab==0 ) goto copy_cleanup;
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v = sqliteGetVdbe(pParse);
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if( v ){
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int openOp;
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@ -16,7 +16,7 @@
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** sqliteRegisterBuildinFunctions() found at the bottom of the file.
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** All other code has file scope.
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**
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** $Id: func.c,v 1.13 2002/03/02 19:00:31 drh Exp $
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** $Id: func.c,v 1.14 2002/03/04 02:26:16 drh Exp $
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*/
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#include <ctype.h>
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#include <math.h>
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@ -242,6 +242,7 @@ struct StdDevCtx {
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double sum2; /* Sum of the squares of terms */
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};
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#if 0 /* Omit because math library is required */
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/*
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** Routines used to compute the standard deviation as an aggregate.
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*/
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@ -263,6 +264,7 @@ static void stdDevFinalize(sqlite_func *context){
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sqrt((p->sum2 - p->sum*p->sum/rN)/(rN-1.0)));
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}
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}
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#endif
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/*
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** The following structure keeps track of state information for the
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@ -396,7 +398,9 @@ void sqliteRegisterBuildinFunctions(sqlite *db){
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{ "avg", 1, sumStep, avgFinalize },
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{ "count", 0, countStep, countFinalize },
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{ "count", 1, countStep, countFinalize },
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#if 0
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{ "stddev", 1, stdDevStep, stdDevFinalize },
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#endif
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};
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int i;
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@ -1,7 +1,7 @@
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#
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# Run this Tcl script to generate the sqlite.html file.
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#
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set rcsid {$Id: c_interface.tcl,v 1.24 2002/02/19 22:42:06 drh Exp $}
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set rcsid {$Id: c_interface.tcl,v 1.25 2002/03/04 02:26:17 drh Exp $}
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puts {<html>
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<head>
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@ -642,6 +642,82 @@ single-quote character ('), it is always a good idea to use the
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SQLite printf routines and the %q formatting option instead of <b>sprintf</b>.
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</p>
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<h2>Adding New SQL Functions</h2>
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<p>Beginning with version 2.4.0, SQLite allows the SQL language to be
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extended with new functions implemented as C code. The following interface
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is used:
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</p>
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<blockquote><pre>
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typedef struct sqlite_func sqlite_func;
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int sqlite_create_function(
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sqlite *db,
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const char *zName,
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int nArg,
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void (*xFunc)(sqlite_func*,int,const char**),
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void *pUserData
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);
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int sqlite_create_aggregate(
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sqlite *db,
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const char *zName,
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int nArg,
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void (*xStep)(sqlite_func*,int,const char**),
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void (*xFinalize)(sqlite_func*),
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void *pUserData
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);
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char *sqlite_set_result_string(sqlite_func*,const char*,int);
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void sqlite_set_result_int(sqlite_func*,int);
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void sqlite_set_result_double(sqlite_func*,double);
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void sqlite_set_result_error(sqlite_func*,const char*,int);
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void *sqlite_user_data(sqlite_func*);
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void *sqlite_aggregate_context(sqlite_func*, int nBytes);
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int sqlite_aggregate_count(sqlite_func*);
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</pre></blockquote>
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<p>
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The <b>sqlite_create_function()</b> interface is used to create
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regular functions and <b>sqlite_create_aggregate()</b> is used to
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create new aggregate functions. In both cases, the <b>db</b>
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parameter is an open SQLite database on which the functions should
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be registered, <b>zName</b> is the name of the new function,
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<b>nArg</b> is the number of arguments, and <b>pUserData</b> is
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a pointer which is passed through unchanged to the C implementation
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of the function.
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</p>
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<p>
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For regular functions, the <b>xFunc</b> callback is invoked once
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for each function call. The implementation of xFunc should call
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one of the <b>sqlite_set_result_...</b> interfaces to return its
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result. The <b>sqlite_user_data()</b> routine can be used to
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retrieve the <b>pUserData</b> pointer that was passed in when the
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function was registered.
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</p>
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<p>
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For aggregate functions, the <b>xStep</b> callback is invoked once
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for each row in the result and then <b>xFinalize</b> is invoked at the
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end to compute a final answer. The xStep routine can use the
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<b>sqlite_aggregate_context()</b> interface to allocate memory that
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will be unique to that particular instance of the SQL function.
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This memory will be automatically deleted after xFinalize is called.
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The <b>sqlite_aggregate_count()</b> routine can be used to find out
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how many rows of data were passed to the aggregate. The xFinalize
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callback should invoke one of the <b>sqlite_set_result_...</b>
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interfaces to set the final result of the aggregate.
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</p>
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<p>
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SQLite now implements all of its built-in functions using this
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interface. For additional information and examples on how to create
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new SQL functions, review the SQLite source code in the file
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<b>func.c</b>.
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</p>
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<h2>Usage Examples</h2>
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<p>For examples of how the SQLite C/C++ interface can be used,
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@ -17,7 +17,7 @@ proc chng {date desc} {
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puts "<DD><P><UL>$desc</UL></P></DD>"
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}
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chng {2002 Feb * (2.3.4)} {
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chng {2002 Mar * (2.4.0)} {
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<li>Change the name of the sanity_check PRAGMA to <b>integrity_check</b>
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and make it available in all compiles.</li>
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<li>SELECT min() or max() of an indexed column with no WHERE or GROUP BY
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@ -28,8 +28,16 @@ chng {2002 Feb * (2.3.4)} {
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<li>Modifications to the "lemon" parser generator so that the parser tables
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are 4 times smaller.</li>
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<li>Added support for user-defined functions implemented in C.</li>
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<li>Added support for new functions: <b>coalesce()</b>, <b>lower()</b>,
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<b>upper()</b>, and <b>random()</b>
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<li>Added support for VIEWs.</li>
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<li>Added the subquery flattening optimizer.</li>
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<li>Modified the B-Tree and Pager modules so that disk pages that do not
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contain real data (free pages) are not journalled and are not
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written from memory back to the disk when they change. This does not
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impact database integrity, since the
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pages contain no real data, but it does make large INSERT operations
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about 2.5 times faster and large DELETEs about 5 times faster.</li>
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}
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chng {2002 Feb 18 (2.3.3)} {
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@ -1,7 +1,7 @@
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#
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# Run this Tcl script to generate the formatchng.html file.
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#
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set rcsid {$Id: formatchng.tcl,v 1.2 2002/01/30 16:17:25 drh Exp $ }
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set rcsid {$Id: formatchng.tcl,v 1.3 2002/03/04 02:26:17 drh Exp $ }
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puts {<html>
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<head>
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@ -89,7 +89,21 @@ occurred since version 1.0.0:
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that are stored in the SQLITE_MASTER table. If you create a database that
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contains this new syntax, then try to read that database using version 2.2.5
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or earlier, the parser will not understand the new syntax and you will get
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an error. Otherwise, databases for 2.2.x and 2.3.x are interchangeable.</p>
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an error. Otherwise, databases for 2.2.x and 2.3.x are interchangeable.</td>
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</tr>
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<tr>
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<td valign="top">2.3.3 to 2.4.0</td>
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<td valign="top">2002-Mar-?</td>
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<td>Beginning with version 2.4.0, SQLite added support for views.
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Information about views is stored in the SQLITE_MASTER table. If an older
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version of SQLite attempts to read a database that contains VIEW information
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in the SQLITE_MASTER table, the parser will not understand the new syntax
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and you will get an error. Also, the
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way SQLite keeps track of unused disk blocks in the database file
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changed slightly.
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If an older version of SQLite attempts to write a database that
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was previously written by version 2.4.0 or later, then it may leak disk
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blocks.</td>
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</tr>
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</table>
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</blockquote>
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172
www/lang.tcl
172
www/lang.tcl
@ -1,7 +1,7 @@
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#
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# Run this Tcl script to generate the sqlite.html file.
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#
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set rcsid {$Id: lang.tcl,v 1.26 2002/02/19 22:42:06 drh Exp $}
|
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set rcsid {$Id: lang.tcl,v 1.27 2002/03/04 02:26:17 drh Exp $}
|
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|
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puts {<html>
|
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<head>
|
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@ -52,6 +52,8 @@ foreach {section} [lsort -index 0 -dictionary {
|
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{{BEGIN TRANSACTION} transaction}
|
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{PRAGMA pragma}
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{{ON CONFLICT clause} conflict}
|
||||
{{CREATE VIEW} createview}
|
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{{DROP VIEW} dropview}
|
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}] {
|
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puts "<li><a href=\"#[lindex $section 1]\">[lindex $section 0]</a></li>"
|
||||
}
|
||||
@ -342,6 +344,21 @@ in place of the original command.
|
||||
</p>
|
||||
}
|
||||
|
||||
Section {CREATE VIEW} {createview}
|
||||
|
||||
Syntax {sql-command} {
|
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CREATE VIEW <view-name> AS <select-statement>
|
||||
}
|
||||
|
||||
puts {
|
||||
<p>The CREATE VIEW command assigns a name to a pre-packaged SELECT
|
||||
statement. Once the view is created, it can be used in the FROM clause
|
||||
of another SELECT in place of a table name.
|
||||
</p>
|
||||
|
||||
<p>You cannot COPY, INSERT or UPDATE a view. Views are read-only.</p>
|
||||
}
|
||||
|
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Section DELETE delete
|
||||
|
||||
Syntax {sql-statement} {
|
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@ -385,6 +402,17 @@ by the name of the table. The table named is completely removed from
|
||||
the disk. The table can not be recovered. All indices associated with
|
||||
the table are also deleted.</p>}
|
||||
|
||||
Section {DROP VIEW} dropview
|
||||
|
||||
Syntax {sql-command} {
|
||||
DROP VIEW <view-name>
|
||||
}
|
||||
|
||||
puts {
|
||||
<p>The DROP VIEW statement consists of the keywords "DROP TABLE" followed
|
||||
by the name of the view. The view named is removed from the database.
|
||||
But no actual data is modified.</p>}
|
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|
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Section EXPLAIN explain
|
||||
|
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Syntax {sql-statement} {
|
||||
@ -420,8 +448,8 @@ Syntax {expression} {
|
||||
<expression> NOTNULL |
|
||||
<expression> [NOT] BETWEEN <expression> AND <expression> |
|
||||
<expression> [NOT] IN ( <value-list> ) |
|
||||
<expression> [NOT] IN ( <select> ) |
|
||||
( <select> )
|
||||
<expression> [NOT] IN ( <select-statement> ) |
|
||||
( <select-statement> )
|
||||
} {like-op} {
|
||||
LIKE | GLOB | NOT LIKE | NOT GLOB
|
||||
}
|
||||
@ -518,37 +546,125 @@ SELECT becomes the value used in the expression. If the SELECT yields
|
||||
more than one result row, all rows after the first are ignored. If
|
||||
the SELECT yeilds no rows, then the value of the SELECT is NULL.</p>
|
||||
|
||||
<p>The expression syntax currently supports the following
|
||||
functions:</p>
|
||||
<p>Both simple and aggregate functions are supported. A simple
|
||||
function can be used in any expression. Simple functions return
|
||||
a result immediately based on their inputs. Aggregate functions
|
||||
may only be used in a SELECT statement. Aggregate functions compute
|
||||
their result across all rows of the result set.</p>
|
||||
|
||||
<blockquote><pre>
|
||||
<font color="#2c2cf0"><big>count min max sum
|
||||
avg length substr abs round</big></font>
|
||||
</pre></blockquote>
|
||||
<p>The following simple functions are currently supported:</p>
|
||||
|
||||
<table border=0 cellpadding=10>
|
||||
<tr>
|
||||
<td valign="top" align="right" width=120>abs(<i>X</i>)</td>
|
||||
<td valign="top">Return the absolute value of argument <i>X</i>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">coelasce(<i>X</i>,<i>Y</i>,...)</td>
|
||||
<td valign="top">Return a copy of the first non-NULL argument. If
|
||||
all arguments are NULL then NULL is returned.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">length(<i>X</i>)</td>
|
||||
<td valign="top">Return the string length of <i>X</i> in characters.
|
||||
If SQLite is configured to support UTF-8, then the number of UTF-8
|
||||
characters is returned, not the number of bytes.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">lower(<i>X</i>)</td>
|
||||
<td valign="top">Return a copy of string <i>X</i> will all characters
|
||||
converted to lower case. The C library <b>tolower()</b> routine is used
|
||||
for the conversion, which means that this function might not
|
||||
work correctly on UTF-8 characters.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">max(<i>X</i>,<i>Y</i>,...)</td>
|
||||
<td valign="top">Return the argument with the maximum value. Arguments
|
||||
may be strings in addition to numbers. The maximum value is determined
|
||||
by the usual sort order. Note that <b>max()</b> is a simple function when
|
||||
it has 2 or more arguments but converts to an aggregate function if given
|
||||
only a single argument.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">min(<i>X</i>,<i>Y</i>,...)</td>
|
||||
<td valign="top">Return the argument with the minimum value. Arguments
|
||||
may be strings in addition to numbers. The mminimum value is determined
|
||||
by the usual sort order. Note that <b>min()</b> is a simple function when
|
||||
it has 2 or more arguments but converts to an aggregate function if given
|
||||
only a single argument.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">random(*)</td>
|
||||
<td valign="top">Return a random integer between -2147483648 and
|
||||
+2147483647.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">round(<i>X</i>)<br>round(<i>X</i>,<i>Y</i>)</td>
|
||||
<td valign="top">Round off the number <i>X</i> to <i>Y</i> digits to the
|
||||
right of the decimal point. If the <i>Y</i> argument is omitted, 0 is
|
||||
assumed.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">subst(<i>X</i>,<i>Y</i>,<i>Z</i>)</td>
|
||||
<td valign="top">Return a substring of input string <i>X</i> that begins
|
||||
with the <i>Y</i>-th character and which is <i>Z</i> characters long.
|
||||
The left-most character of <i>X</i> is number 1. If <i>Y</i> is negative
|
||||
the the first character of the substring is found by counting from the
|
||||
right rather than the left. If SQLite is configured to support UTF-8,
|
||||
then characters indices refer to actual UTF-8 characters, not bytes.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">upper(<i>X</i>)</td>
|
||||
<td valign="top">Return a copy of input string <i>X</i> converted to all
|
||||
upper-case letters. The implementation of this function uses the C library
|
||||
routine <b>toupper()</b> which means it may not work correctly on
|
||||
UTF-8 strings.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>
|
||||
The functions <b>count</b>, <b>sum</b>, and <b>avg</b> and the functions
|
||||
<b>min</b> and <b>max</b> used with only one argument are all aggregate
|
||||
functions. This means that they are computed across all rows of the result.
|
||||
The functions <b>min</b> and <b>max</b>
|
||||
with two or more arguments and all other functions
|
||||
are non-aggregates. Non-aggregate functions
|
||||
are computed separately for each row of the result.
|
||||
The following aggregate functions are supported:
|
||||
</p>
|
||||
|
||||
<p>
|
||||
The <b>round</b> function can take either 1 or 2 arguments. The
|
||||
first argument is the floating point value that is rounded. The
|
||||
second argument is the number of digits to the right of the
|
||||
decimal point to preserve. If the second argument is omitted,
|
||||
zero is assumed. So round(1.23456,2) is 1.23 and
|
||||
round(12.34,0) and round(12.34) both evaluate to 12.
|
||||
</p>
|
||||
<table border=0 cellpadding=10>
|
||||
<tr>
|
||||
<td valign="top" align="right" width=120>avg(<i>X</i>)</td>
|
||||
<td valign="top">Return the average value of all <i>X</i> within a group.</td>
|
||||
</tr>
|
||||
|
||||
<p>
|
||||
The "<b>count(*)</b>" syntax is supported but
|
||||
"<b>count(distinct</b> <i>COLUMN-NAME</i><b>)</b>" is not.
|
||||
</p>
|
||||
<tr>
|
||||
<td valign="top" align="right">count(<i>X</i>)<br>count(*)</td>
|
||||
<td valign="top">The first form return a count of the number of times
|
||||
that <i>X</i> is not NULL in a group. The second form (with no argument)
|
||||
returns the total number of rows in the group.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">max(<i>X</i>)</td>
|
||||
<td valign="top">Return the maximum value of all values in the group.
|
||||
The usual sort order is used to determine the maximum.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">min(<i>X</i>)</td>
|
||||
<td valign="top">Return the minimum value of all values in the group.
|
||||
The usual sort order is used to determine the minimum.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">sum(<i>X</i>)</td>
|
||||
<td valign="top">Return the numeric sum of all values in the group.</td>
|
||||
</tr>
|
||||
</table>
|
||||
}
|
||||
|
||||
Section INSERT insert
|
||||
|
||||
Loading…
Reference in New Issue
Block a user