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Diffstat (limited to 'ext/expert/expert.c')
| -rw-r--r-- | ext/expert/expert.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/ext/expert/expert.c b/ext/expert/expert.c new file mode 100644 index 0000000..051480f --- /dev/null +++ b/ext/expert/expert.c @@ -0,0 +1,156 @@ +/* +** 2017 April 07 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +*/ + + +#include <sqlite3.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "sqlite3expert.h" + + +static void option_requires_argument(const char *zOpt){ + fprintf(stderr, "Option requires an argument: %s\n", zOpt); + exit(-3); +} + +static int option_integer_arg(const char *zVal){ + return atoi(zVal); +} + +static void usage(char **argv){ + fprintf(stderr, "\n"); + fprintf(stderr, "Usage %s ?OPTIONS? DATABASE\n", argv[0]); + fprintf(stderr, "\n"); + fprintf(stderr, "Options are:\n"); + fprintf(stderr, " -sql SQL (analyze SQL statements passed as argument)\n"); + fprintf(stderr, " -file FILE (read SQL statements from file FILE)\n"); + fprintf(stderr, " -verbose LEVEL (integer verbosity level. default 1)\n"); + fprintf(stderr, " -sample PERCENT (percent of db to sample. default 100)\n"); + exit(-1); +} + +static int readSqlFromFile(sqlite3expert *p, const char *zFile, char **pzErr){ + FILE *in = fopen(zFile, "rb"); + long nIn; + size_t nRead; + char *pBuf; + int rc; + if( in==0 ){ + *pzErr = sqlite3_mprintf("failed to open file %s\n", zFile); + return SQLITE_ERROR; + } + fseek(in, 0, SEEK_END); + nIn = ftell(in); + rewind(in); + pBuf = sqlite3_malloc64( nIn+1 ); + nRead = fread(pBuf, nIn, 1, in); + fclose(in); + if( nRead!=1 ){ + sqlite3_free(pBuf); + *pzErr = sqlite3_mprintf("failed to read file %s\n", zFile); + return SQLITE_ERROR; + } + pBuf[nIn] = 0; + rc = sqlite3_expert_sql(p, pBuf, pzErr); + sqlite3_free(pBuf); + return rc; +} + +int main(int argc, char **argv){ + const char *zDb; + int rc = 0; + char *zErr = 0; + int i; + int iVerbose = 1; /* -verbose option */ + + sqlite3 *db = 0; + sqlite3expert *p = 0; + + if( argc<2 ) usage(argv); + zDb = argv[argc-1]; + if( zDb[0]=='-' ) usage(argv); + rc = sqlite3_open(zDb, &db); + if( rc!=SQLITE_OK ){ + fprintf(stderr, "Cannot open db file: %s - %s\n", zDb, sqlite3_errmsg(db)); + exit(-2); + } + + p = sqlite3_expert_new(db, &zErr); + if( p==0 ){ + fprintf(stderr, "Cannot run analysis: %s\n", zErr); + rc = 1; + }else{ + for(i=1; i<(argc-1); i++){ + char *zArg = argv[i]; + int nArg; + if( zArg[0]=='-' && zArg[1]=='-' && zArg[2]!=0 ) zArg++; + nArg = (int)strlen(zArg); + if( nArg>=2 && 0==sqlite3_strnicmp(zArg, "-file", nArg) ){ + if( ++i==(argc-1) ) option_requires_argument("-file"); + rc = readSqlFromFile(p, argv[i], &zErr); + } + + else if( nArg>=3 && 0==sqlite3_strnicmp(zArg, "-sql", nArg) ){ + if( ++i==(argc-1) ) option_requires_argument("-sql"); + rc = sqlite3_expert_sql(p, argv[i], &zErr); + } + + else if( nArg>=3 && 0==sqlite3_strnicmp(zArg, "-sample", nArg) ){ + int iSample; + if( ++i==(argc-1) ) option_requires_argument("-sample"); + iSample = option_integer_arg(argv[i]); + sqlite3_expert_config(p, EXPERT_CONFIG_SAMPLE, iSample); + } + + else if( nArg>=2 && 0==sqlite3_strnicmp(zArg, "-verbose", nArg) ){ + if( ++i==(argc-1) ) option_requires_argument("-verbose"); + iVerbose = option_integer_arg(argv[i]); + } + + else{ + usage(argv); + } + } + } + + if( rc==SQLITE_OK ){ + rc = sqlite3_expert_analyze(p, &zErr); + } + + if( rc==SQLITE_OK ){ + int nQuery = sqlite3_expert_count(p); + if( iVerbose>0 ){ + const char *zCand = sqlite3_expert_report(p,0,EXPERT_REPORT_CANDIDATES); + fprintf(stdout, "-- Candidates -------------------------------\n"); + fprintf(stdout, "%s\n", zCand); + } + for(i=0; i<nQuery; i++){ + const char *zSql = sqlite3_expert_report(p, i, EXPERT_REPORT_SQL); + const char *zIdx = sqlite3_expert_report(p, i, EXPERT_REPORT_INDEXES); + const char *zEQP = sqlite3_expert_report(p, i, EXPERT_REPORT_PLAN); + if( zIdx==0 ) zIdx = "(no new indexes)\n"; + if( iVerbose>0 ){ + fprintf(stdout, "-- Query %d ----------------------------------\n",i+1); + fprintf(stdout, "%s\n\n", zSql); + } + fprintf(stdout, "%s\n%s\n", zIdx, zEQP); + } + }else{ + fprintf(stderr, "Error: %s\n", zErr ? zErr : "?"); + } + + sqlite3_expert_destroy(p); + sqlite3_free(zErr); + return rc; +} |