diff options
Diffstat (limited to 'contrib/fulltextindex/fti.c')
| -rw-r--r-- | contrib/fulltextindex/fti.c | 258 |
1 files changed, 139 insertions, 119 deletions
diff --git a/contrib/fulltextindex/fti.c b/contrib/fulltextindex/fti.c index e5539b4457..0291a48a27 100644 --- a/contrib/fulltextindex/fti.c +++ b/contrib/fulltextindex/fti.c @@ -1,18 +1,18 @@ #include "postgres.h" #include "executor/spi.h" #include "commands/trigger.h" -#include <ctype.h> /* tolower */ -#include <stdio.h> /* debugging */ +#include <ctype.h> /* tolower */ +#include <stdio.h> /* debugging */ /* * Trigger function takes 2 arguments: - 1. relation in which to store the substrings - 2. field to extract substrings from + 1. relation in which to store the substrings + 2. field to extract substrings from The relation in which to insert *must* have the following layout: - string varchar(#) - id oid + string varchar(#) + id oid Example: @@ -24,9 +24,9 @@ create index title_fti_idx on title_fti (string); create trigger title_fti_trigger after update or insert or delete on product for each row execute procedure fti(title_fti, title); - ^^^^^^^^^ + ^^^^^^^^^ where to store index in - ^^^^^ + ^^^^^ which column to index ofcourse don't forget to create an index on title_idx, column string, else @@ -39,8 +39,8 @@ select p.* from product p, title_fti f1, title_fti f2 where */ /* - march 4 1998 Changed breakup() to return less substrings. Only breakup - in word parts which are in turn shortened from the start + march 4 1998 Changed breakup() to return less substrings. Only breakup + in word parts which are in turn shortened from the start of the word (ie. word, ord, rd) Did allocation of substring buffer outside of breakup() oct. 5 1997, fixed a bug in string breakup (where there are more nonalpha @@ -62,14 +62,14 @@ select p.* from product p, title_fti f1, title_fti f2 where */ HeapTuple fti(void); -char *breakup(char*, char*); -bool is_stopword(char*); +char *breakup(char *, char *); +bool is_stopword(char *); -bool new_tuple = false; +bool new_tuple = false; /* THIS LIST MUST BE IN SORTED ORDER, A BINARY SEARCH IS USED!!!! */ -char *StopWords[] = { /* list of words to skip in indexing */ +char *StopWords[] = { /* list of words to skip in indexing */ #ifdef SAMPLE_STOP_WORDS "no" "the", @@ -88,7 +88,7 @@ typedef struct static EPlan *InsertPlans = NULL; static EPlan *DeletePlans = NULL; static int nInsertPlans = 0; -static int nDeletePlans = 0; +static int nDeletePlans = 0; static EPlan *find_plan(char *ident, EPlan ** eplan, int *nplans); @@ -96,28 +96,28 @@ static EPlan *find_plan(char *ident, EPlan ** eplan, int *nplans); HeapTuple fti() { - Trigger *trigger; /* to get trigger name */ - int nargs; /* # of arguments */ - char **args; /* arguments */ - char *relname; /* triggered relation name */ - Relation rel; /* triggered relation */ - char *indexname; /* name of table for substrings */ + Trigger *trigger; /* to get trigger name */ + int nargs; /* # of arguments */ + char **args; /* arguments */ + char *relname; /* triggered relation name */ + Relation rel; /* triggered relation */ + char *indexname; /* name of table for substrings */ HeapTuple rettuple = NULL; - TupleDesc tupdesc; /* tuple description */ - bool isinsert=false; - bool isdelete=false; + TupleDesc tupdesc; /* tuple description */ + bool isinsert = false; + bool isdelete = false; int ret; char query[8192]; Oid oid; + /* - FILE *debug; - */ + * FILE *debug; + */ /* - debug = fopen("/dev/xconsole", "w"); - fprintf(debug, "FTI: entered function\n"); - fflush(debug); - */ + * debug = fopen("/dev/xconsole", "w"); fprintf(debug, "FTI: entered + * function\n"); fflush(debug); + */ if (!CurrentTriggerData) elog(ERROR, "Full Text Indexing: triggers are not initialized"); @@ -127,47 +127,53 @@ fti() elog(ERROR, "Full Text Indexing: must be fired AFTER event"); if (TRIGGER_FIRED_BY_INSERT(CurrentTriggerData->tg_event)) - isinsert=true; + isinsert = true; if (TRIGGER_FIRED_BY_UPDATE(CurrentTriggerData->tg_event)) - { isdelete=true;isinsert=true;} + { + isdelete = true; + isinsert = true; + } if (TRIGGER_FIRED_BY_DELETE(CurrentTriggerData->tg_event)) - isdelete=true; + isdelete = true; trigger = CurrentTriggerData->tg_trigger; rel = CurrentTriggerData->tg_relation; relname = SPI_getrelname(rel); - rettuple=CurrentTriggerData->tg_trigtuple; - if (isdelete&&isinsert) /* is an UPDATE */ - rettuple=CurrentTriggerData->tg_newtuple; + rettuple = CurrentTriggerData->tg_trigtuple; + if (isdelete && isinsert) /* is an UPDATE */ + rettuple = CurrentTriggerData->tg_newtuple; - CurrentTriggerData = NULL; /* invalidate 'normal' calls to this function */ + CurrentTriggerData = NULL; /* invalidate 'normal' calls to this + * function */ + + if ((ret = SPI_connect()) < 0) + elog(ERROR, "Full Text Indexing: SPI_connect failed, returned %d\n", ret); - if ((ret = SPI_connect()) <0) - elog(ERROR,"Full Text Indexing: SPI_connect failed, returned %d\n",ret); - nargs = trigger->tgnargs; if (nargs != 2) elog(ERROR, "Full Text Indexing: trigger can only have 2 arguments"); - + args = trigger->tgargs; indexname = args[0]; - tupdesc = rel->rd_att; /* what the tuple looks like (?) */ + tupdesc = rel->rd_att; /* what the tuple looks like (?) */ /* get oid of current tuple, needed by all, so place here */ oid = rettuple->t_data->t_oid; if (!OidIsValid(oid)) - elog(ERROR,"Full Text Indexing: oid of current tuple is NULL"); + elog(ERROR, "Full Text Indexing: oid of current tuple is NULL"); - if (isdelete) { - void *pplan; - Oid *argtypes; - Datum values[1]; - EPlan *plan; + if (isdelete) + { + void *pplan; + Oid *argtypes; + Datum values[1]; + EPlan *plan; sprintf(query, "D%s$%s", args[0], args[1]); plan = find_plan(query, &DeletePlans, &nDeletePlans); - if (plan->nplans <= 0) { - argtypes = (Oid *)palloc(sizeof(Oid)); + if (plan->nplans <= 0) + { + argtypes = (Oid *) palloc(sizeof(Oid)); argtypes[0] = OIDOID; @@ -181,7 +187,7 @@ fti() elog(ERROR, "Full Text Indexing: SPI_saveplan returned NULL " "in delete"); - plan->splan = (void **)malloc(sizeof(void*)); + plan->splan = (void **) malloc(sizeof(void *)); *(plan->splan) = pplan; plan->nplans = 1; } @@ -192,26 +198,29 @@ fti() if (ret != SPI_OK_DELETE) elog(ERROR, "Full Text Indexing: error executing plan in delete"); } - - if (isinsert) { - char *substring, *column; - void *pplan; - Oid *argtypes; - Datum values[2]; - int colnum; + + if (isinsert) + { + char *substring, + *column; + void *pplan; + Oid *argtypes; + Datum values[2]; + int colnum; struct varlena *data; - EPlan *plan; + EPlan *plan; sprintf(query, "I%s$%s", args[0], args[1]); plan = find_plan(query, &InsertPlans, &nInsertPlans); /* no plan yet, so allocate mem for argtypes */ - if (plan->nplans <= 0) { - argtypes = (Oid *)palloc(2*sizeof(Oid)); + if (plan->nplans <= 0) + { + argtypes = (Oid *) palloc(2 * sizeof(Oid)); - argtypes[0] = VARCHAROID; /*create table t_name - (string varchar, */ - argtypes[1] = OIDOID; /* id oid); */ + argtypes[0] = VARCHAROID; /* create table t_name (string + * varchar, */ + argtypes[1] = OIDOID; /* id oid); */ /* prepare plan to gain speed */ sprintf(query, "INSERT INTO %s (string, id) VALUES ($1, $2)", @@ -226,45 +235,49 @@ fti() elog(ERROR, "Full Text Indexing: SPI_saveplan returned NULL" " in insert"); - plan->splan = (void **)malloc(sizeof(void*)); + plan->splan = (void **) malloc(sizeof(void *)); *(plan->splan) = pplan; plan->nplans = 1; } - - + + /* prepare plan for query */ - colnum=SPI_fnumber(tupdesc, args[1]); + colnum = SPI_fnumber(tupdesc, args[1]); if (colnum == SPI_ERROR_NOATTRIBUTE) elog(ERROR, "Full Text Indexing: column '%s' of '%s' not found", args[1], args[0]); - + /* Get the char* representation of the column with name args[1] */ column = SPI_getvalue(rettuple, tupdesc, colnum); - - if (column) { /* make sure we don't try to index NULL's */ - char *buff; - char *string = column; - - while(*string != '\0') { /* placed 'really' inline. */ - *string = tolower(*string); /* some compilers will choke */ - string++; /* on 'inline' keyword */ + + if (column) + { /* make sure we don't try to index NULL's */ + char *buff; + char *string = column; + + while (*string != '\0') + { /* placed 'really' inline. */ + *string = tolower(*string); /* some compilers will + * choke */ + string++; /* on 'inline' keyword */ } - data = (struct varlena*)palloc(sizeof(int32)+strlen(column)+1); + data = (struct varlena *) palloc(sizeof(int32) + strlen(column) +1); buff = palloc(strlen(column) + 1); - /* saves lots of calls in while-loop and in breakup()*/ + /* saves lots of calls in while-loop and in breakup() */ - new_tuple=true; - while ((substring = breakup(column, buff))) { - int l; + new_tuple = true; + while ((substring = breakup(column, buff))) + { + int l; l = strlen(substring); - data->vl_len = l+sizeof(int32); + data->vl_len = l + sizeof(int32); memcpy(VARDATA(data), substring, l); values[0] = PointerGetDatum(data); values[1] = oid; - + ret = SPI_execp(*(plan->splan), values, NULL, 0); if (ret != SPI_OK_INSERT) elog(ERROR, "Full Text Indexing: error executing plan " @@ -279,76 +292,83 @@ fti() return (rettuple); } -char *breakup(char *string, char *substring) +char * +breakup(char *string, char *substring) { static char *last_start; static char *cur_pos; if (new_tuple) { - cur_pos=last_start=&string[strlen(string)-1]; - new_tuple=false; /* don't initialize this next time */ + cur_pos = last_start = &string[strlen(string) - 1]; + new_tuple = false; /* don't initialize this next time */ } - while (cur_pos > string) /* don't read before start of 'string' */ + while (cur_pos > string) /* don't read before start of 'string' */ { - /* skip pieces at the end of a string that are not - alfa-numeric (ie. 'string$%^&', last_start first points to - '&', and after this to 'g' */ - if (!isalnum((int)*last_start)) { - while (!isalnum((int)*last_start) && + + /* + * skip pieces at the end of a string that are not alfa-numeric + * (ie. 'string$%^&', last_start first points to '&', and after + * this to 'g' + */ + if (!isalnum((int) *last_start)) + { + while (!isalnum((int) *last_start) && last_start > string) last_start--; - cur_pos=last_start; + cur_pos = last_start; } - cur_pos--; /* substrings are at minimum 2 characters long */ + cur_pos--; /* substrings are at minimum 2 characters + * long */ - if (isalnum((int)*cur_pos)) + if (isalnum((int) *cur_pos)) { /* Houston, we have a substring! :) */ memcpy(substring, cur_pos, last_start - cur_pos + 1); - substring[last_start-cur_pos+1]='\0'; - if (!is_stopword(substring)) return substring; + substring[last_start - cur_pos + 1] = '\0'; + if (!is_stopword(substring)) + return substring; } else { - last_start=cur_pos-1; + last_start = cur_pos - 1; cur_pos = last_start; } } - return NULL; /* we've processed all of 'string' */ + return NULL; /* we've processed all of 'string' */ } /* copied from src/backend/parser/keywords.c and adjusted for our situation*/ bool is_stopword(char *text) { - char **StopLow; /* for list of stop-words */ - char **StopHigh; - char **StopMiddle; - unsigned int difference; + char **StopLow; /* for list of stop-words */ + char **StopHigh; + char **StopMiddle; + unsigned int difference; - StopLow = &StopWords[0]; /* initialize stuff for binary search */ + StopLow = &StopWords[0]; /* initialize stuff for binary search */ StopHigh = endof(StopWords); if (lengthof(StopWords) == 0) return false; - - while (StopLow <= StopHigh) - { - StopMiddle = StopLow + (StopHigh - StopLow) / 2; - difference = strcmp(*StopMiddle, text); - if (difference == 0) - return (true); - else if (difference < 0) - StopLow = StopMiddle + 1; - else - StopHigh = StopMiddle - 1; - } - - return (false); + + while (StopLow <= StopHigh) + { + StopMiddle = StopLow + (StopHigh - StopLow) / 2; + difference = strcmp(*StopMiddle, text); + if (difference == 0) + return (true); + else if (difference < 0) + StopLow = StopMiddle + 1; + else + StopHigh = StopMiddle - 1; + } + + return (false); } /* for caching of query plans, stolen from contrib/spi/\*.c */ |