postgres/src/bin/psql/describe.c

#include <config.h>
#include <c.h>
#include "describe.h"

#include <string.h>

#include <postgres.h>     /* for VARHDRSZ, int4 type */
#include <postgres_ext.h>
#include <libpq-fe.h>

#include "common.h"
#include "settings.h"
#include "print.h"
#include "variables.h"


/*----------------
 * Handlers for various slash commands displaying some sort of list
 * of things in the database.
 *
 * If you add something here, consider this:
 * - If (and only if) the variable "description" is set, the description/
 *   comment for the object should be displayed.
 * - Try to format the query to look nice in -E output.
 *----------------
 */

/* the maximal size of regular expression we'll accept here */
/* (it is save to just change this here) */
#define REGEXP_CUTOFF 10 * NAMEDATALEN


/* \da
 * takes an optional regexp to match specific aggregates by name
 */
bool
describeAggregates(const char * name, PsqlSettings * pset)
{
    char descbuf[384 + 2*REGEXP_CUTOFF];  /* observe/adjust this if you change the query */
    PGresult * res;
    bool description = GetVariableBool(pset->vars, "description");
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';

    /* There are two kinds of aggregates: ones that work on particular types
       ones that work on all */
    strcat(descbuf,
	   "SELECT a.aggname AS \"Name\", t.typname AS \"Type\"");
    if (description)
	strcat(descbuf, 
           ",\n       obj_description(a.oid) as \"Description\"");
    strcat(descbuf,
	   "\nFROM pg_aggregate a, pg_type t\n"
	   "WHERE a.aggbasetype = t.oid\n");
    if (name) {
	strcat(descbuf, "  AND a.aggname ~* '^");
	strncat(descbuf, name, REGEXP_CUTOFF);
	strcat(descbuf, "'\n");
    }

    strcat(descbuf,
	   "UNION\n"
	   "SELECT a.aggname AS \"Name\", '(all types)' as \"Type\"");
    if (description)
	strcat(descbuf, 
           ",\n       obj_description(a.oid) as \"Description\"");
    strcat(descbuf,
	   "\nFROM pg_aggregate a\n"
	   "WHERE a.aggbasetype = 0\n");
    if (name)
    {
	strcat(descbuf, "  AND a.aggname ~* '^");
	strncat(descbuf, name, REGEXP_CUTOFF);
	strcat(descbuf, "'\n");
    }

    strcat(descbuf, "ORDER BY \"Name\", \"Type\"");

    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    myopt.topt.tuples_only = false;
    myopt.nullPrint = NULL;
    myopt.title = "List of aggregates";

    printQuery(res, &myopt, pset->queryFout);

    PQclear(res);
    return true;
}


/* \df
 * takes an optional regexp to narrow down the function name
 */
bool
describeFunctions(const char * name, PsqlSettings * pset)
{
    char descbuf[384 + REGEXP_CUTOFF];
    PGresult * res;
    printQueryOpt myopt = pset->popt;

    /*
     * we skip in/out funcs by excluding functions that take
     * some arguments, but have no types defined for those
     * arguments
     */
    descbuf[0] = '\0';

    strcat(descbuf, "SELECT t.typname as \"Result\", p.proname as \"Function\",\n"
                    "       oid8types(p.proargtypes) as \"Arguments\"");
    if (GetVariableBool(pset->vars, "description"))
	strcat(descbuf, "\n,       obj_description(p.oid) as \"Description\"");
    strcat(descbuf, "\nFROM pg_proc p, pg_type t\n"
	            "WHERE p.prorettype = t.oid and (pronargs = 0 or oid8types(p.proargtypes) != '')\n");
    if (name)
    {
	strcat(descbuf, "  AND p.proname ~* '^");
	strncat(descbuf, name, REGEXP_CUTOFF);
	strcat(descbuf, "'\n");
    }
    strcat(descbuf, "ORDER BY \"Function\", \"Result\", \"Arguments\"");

    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    myopt.topt.tuples_only = false;
    myopt.nullPrint = NULL;
    myopt.title = "List of functions";

    printQuery(res, &myopt, pset->queryFout);

    PQclear(res);
    return true;
}



/*
 * describeTypes
 *
 * for \dT
 */
bool
describeTypes(const char * name, PsqlSettings * pset)
{
    char descbuf[256 + REGEXP_CUTOFF];
    PGresult * res;
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';
    strcat(descbuf, "SELECT typname AS \"Type\"");
    if (GetVariableBool(pset->vars, "description"))
	strcat(descbuf, ", obj_description(p.oid) as \"Description\"");
    strcat(descbuf, "\nFROM pg_type\n"
	            "WHERE typrelid = 0 AND typname !~ '^_.*'\n");

    if (name) {
	strcat(descbuf, "  AND typname ~* '^");
	strncat(descbuf, name, REGEXP_CUTOFF);
	strcat(descbuf, "' ");
    }
    strcat(descbuf, "ORDER BY typname;");
	
    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    myopt.topt.tuples_only = false;
    myopt.nullPrint = NULL;
    myopt.title = "List of types";

    printQuery(res, &myopt, pset->queryFout);

    PQclear(res);
    return true;
}



/* \do
 * NOTE: The (optional) argument here is _not_ a regexp since with all the
 * funny chars floating around that would probably confuse people. It's an
 * exact match string.
 */
bool
describeOperators(const char * name, PsqlSettings * pset)
{
    char descbuf[1536 + 3 * 32]; /* 32 is max length for operator name */
    PGresult * res;
    bool description = GetVariableBool(pset->vars, "description");
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';

    strcat(descbuf, "SELECT o.oprname AS \"Op\",\n"
                    "       t1.typname AS \"Left arg\",\n"
                    "       t2.typname AS \"Right arg\",\n"
                    "       t0.typname AS \"Result\"");
    if (description)
	strcat(descbuf, ",\n       obj_description(p.oid) as \"Description\"");
    strcat(descbuf, "\nFROM   pg_proc p, pg_type t0,\n"
                    "       pg_type t1, pg_type t2,\n"
                    "       pg_operator o\n"
                    "WHERE  p.prorettype = t0.oid AND\n"
                    "       RegprocToOid(o.oprcode) = p.oid AND\n"
                    "       p.pronargs = 2 AND\n"
                    "       o.oprleft = t1.oid AND\n"
                    "       o.oprright = t2.oid\n");
    if (name)
    {
	strcat(descbuf, "  AND o.oprname = '");
	strncat(descbuf, name, 32);
	strcat(descbuf, "'\n");
    }

    strcat(descbuf, "\nUNION\n\n"
                    "SELECT o.oprname as \"Op\",\n"
                    "       ''::name AS \"Left arg\",\n"
                    "       t1.typname AS \"Right arg\",\n"
                    "       t0.typname AS \"Result\"");
    if (description)
	strcat(descbuf, ",\n       obj_description(p.oid) as \"Description\"");
    strcat(descbuf, "\nFROM   pg_operator o, pg_proc p, pg_type t0, pg_type t1\n"
                    "WHERE  RegprocToOid(o.oprcode) = p.oid AND\n"
                    "       o.oprresult = t0.oid AND\n"
                    "       o.oprkind = 'l' AND\n"
                    "       o.oprright = t1.oid\n");
    if (name)
    {
	strcat(descbuf, "AND o.oprname = '");
	strncat(descbuf, name, 32);
	strcat(descbuf, "'\n");
    }

    strcat(descbuf, "\nUNION\n\n"
                    "SELECT o.oprname  as \"Op\",\n"
                    "       t1.typname AS \"Left arg\",\n"
                    "       ''::name AS \"Right arg\",\n"
                    "       t0.typname AS \"Result\"");
    if (description)
	strcat(descbuf, ",\n       obj_description(p.oid) as \"Description\"");
    strcat(descbuf, "\nFROM   pg_operator o, pg_proc p, pg_type t0, pg_type t1\n"
                    "WHERE  RegprocToOid(o.oprcode) = p.oid AND\n"
                    "       o.oprresult = t0.oid AND\n"
                    "       o.oprkind = 'r' AND\n"
                    "       o.oprleft = t1.oid\n");
    if (name)
    {
	strcat(descbuf, "AND o.oprname = '");
	strncat(descbuf, name, 32);
	strcat(descbuf, "'\n");
    }
    strcat(descbuf, "\nORDER BY \"Op\", \"Left arg\", \"Right arg\", \"Result\"");

    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    myopt.topt.tuples_only = false;
    myopt.nullPrint = NULL;
    myopt.title = "List of operators";

    printQuery(res, &myopt, pset->queryFout);

    PQclear(res);
    return true;
}


/*
 * listAllDbs
 *
 * for \l, \list, and -l switch
 */
bool
listAllDbs(PsqlSettings *pset)
{
    PGresult *res;
    char descbuf[256];
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';
    strcat(descbuf, "SELECT pg_database.datname as \"Database\",\n"
                    "       pg_user.usename as \"Owner\""
#ifdef MULTIBYTE
	            ",\n       pg_database.encoding as \"Encoding\""
#endif
	   );
    if (GetVariableBool(pset->vars, "description"))
	strcat(descbuf, ",\n       obj_description(pg_database.oid) as \"Description\"\n");
    strcat(descbuf, "FROM pg_database, pg_user\n"
	            "WHERE pg_database.datdba = pg_user.usesysid\n"
                    "ORDER BY \"Database\"");

    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    myopt.topt.tuples_only = false;
    myopt.nullPrint = NULL;
    myopt.title = "List of databases";

    printQuery(res, &myopt, pset->queryFout);

    PQclear(res);
    return true;
}


/* List Tables Grant/Revoke Permissions
 * \z (now also \dp -- perhaps more mnemonic)
 * 
 */
bool
permissionsList(const char * name, PsqlSettings *pset)
{
    char      descbuf[256 + REGEXP_CUTOFF];
    PGresult  *res;
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';
    /* Currently, we ignore indexes since they have no meaningful rights */
    strcat(descbuf, "SELECT relname as \"Relation\",\n"
	            "       relacl as \"Access permissions\"\n"
	            "FROM   pg_class\n"
	            "WHERE  ( relkind = 'r' OR relkind = 'S') AND\n"
	            "       relname !~ '^pg_'\n");
    if (name) {
	strcat(descbuf, "  AND rename ~ '^");
	strncat(descbuf, name, REGEXP_CUTOFF);
	strcat(descbuf, "'\n");
    }
    strcat (descbuf, "ORDER BY relname");

    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    if (PQntuples(res) == 0) {
	fputs("Couldn't find any tables.\n", pset->queryFout);
    }
    else {
	myopt.topt.tuples_only = false;
	myopt.nullPrint = NULL;
	sprintf(descbuf, "Access permissions for database \"%s\"", PQdb(pset->db));
	myopt.title = descbuf;

	printQuery(res, &myopt, pset->queryFout);
    }

    PQclear(res);
    return true;
}




/*
 * Get object comments
 *
 * \dd [foo]
 *
 * Note: This only lists things that actually have a description. For complete
 * lists of things, there are other \d? commands.
 */
bool
objectDescription(const char * object, PsqlSettings *pset)
{
    char       descbuf[2048 + 7*REGEXP_CUTOFF];
    PGresult   *res;
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';

    /* Aggregate descriptions */
    strcat(descbuf, "SELECT DISTINCT a.aggname as \"Name\", 'aggregate'::text as \"What\", d.description as \"Description\"\n"
	            "FROM pg_aggregate a, pg_description d\n"
                    "WHERE a.oid = d.objoid\n");
    if (object) {
	strcat(descbuf,"  AND a.aggname ~* '^");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    /* Function descriptions (except in/outs for datatypes) */
    strcat(descbuf, "\nUNION ALL\n\n");
    strcat(descbuf, "SELECT DISTINCT p.proname as \"Name\", 'function'::text as \"What\", d.description as \"Description\"\n"
	            "FROM pg_proc p, pg_description d\n"
                    "WHERE p.oid = d.objoid AND (p.pronargs = 0 or oid8types(p.proargtypes) != '')\n");
    if (object) {
	strcat(descbuf,"  AND p.proname ~* '^");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    /* Operator descriptions */
    strcat(descbuf, "\nUNION ALL\n\n");
    strcat(descbuf, "SELECT DISTINCT o.oprname as \"Name\", 'operator'::text as \"What\", d.description as \"Description\"\n"
                    "FROM pg_operator o, pg_description d\n"
	   // must get comment via associated function
                    "WHERE RegprocToOid(o.oprcode) = d.objoid\n");
    if (object) {
	strcat(descbuf,"  AND o.oprname = '");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    /* Type description */
    strcat(descbuf, "\nUNION ALL\n\n");
    strcat(descbuf, "SELECT DISTINCT t.typname as \"Name\", 'type'::text as \"What\", d.description as \"Description\"\n"
	            "FROM pg_type t, pg_description d\n"
                    "WHERE t.oid = d.objoid\n");
    if (object) {
	strcat(descbuf,"  AND t.typname ~* '^");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    /* Relation (tables, views, indices, sequences) descriptions */
    strcat(descbuf, "\nUNION ALL\n\n");
    strcat(descbuf, "SELECT DISTINCT c.relname as \"Name\", 'relation'::text||'('||c.relkind||')' as \"What\", d.description as \"Description\"\n"
	            "FROM pg_class c, pg_description d\n"
                    "WHERE c.oid = d.objoid\n");
    if (object) {
	strcat(descbuf,"  AND c.relname ~* '^");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    /* Rule description (ignore rules for views) */
    strcat(descbuf, "\nUNION ALL\n\n");
    strcat(descbuf, "SELECT DISTINCT r.rulename as \"Name\", 'rule'::text as \"What\", d.description as \"Description\"\n"
	            "FROM pg_rewrite r, pg_description d\n"
                    "WHERE r.oid = d.objoid AND r.rulename !~ '^_RET'\n");
    if (object) {
	strcat(descbuf,"  AND r.rulename ~* '^");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    /* Trigger description */
    strcat(descbuf, "\nUNION ALL\n\n");
    strcat(descbuf, "SELECT DISTINCT t.tgname as \"Name\", 'trigger'::text as \"What\", d.description as \"Description\"\n"
	            "FROM pg_trigger t, pg_description d\n"
                    "WHERE t.oid = d.objoid\n");
    if (object) {
	strcat(descbuf,"  AND t.tgname ~* '^");
	strncat(descbuf, object, REGEXP_CUTOFF);
	strcat(descbuf,"'\n");
    }

    strcat(descbuf, "\nORDER BY \"Name\"");


    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    myopt.topt.tuples_only = false;
    myopt.nullPrint = NULL;
    myopt.title = "Object descriptions";

    printQuery(res, &myopt, pset->queryFout);

    PQclear(res);
    return true;
}



/*
 * describeTableDetails (for \d)
 *
 * Unfortunately, the information presented here is so complicated that it
 * be done in a single query. So we have to assemble the printed table by hand
 * and pass it to the underlying printTable() function.
 *
 */
static void * xmalloc(size_t size)
{
    void * tmp;
    tmp = malloc(size);
    if (!tmp) {
	perror("malloc");
	exit(EXIT_FAILURE);
    }
    return tmp;
}


bool
describeTableDetails(const char * name, PsqlSettings * pset)
{
    char          descbuf[512 + NAMEDATALEN];
    PGresult      *res = NULL, *res2 = NULL, *res3 = NULL;
    printTableOpt myopt = pset->popt.topt;
    bool          description = GetVariableBool(pset->vars, "description");
    int i;
    char          * view_def = NULL;
    char          * headers[5];
    char          ** cells = NULL;
    char          * title = NULL;
    char          ** footers = NULL;
    char ** ptr;
    unsigned int  cols;

    cols = 3 + (description ? 1 : 0);

    headers[0] = "Attribute";
    headers[1] = "Type";
    headers[2] = "Info";
    if (description) {
	headers[3] = "Description";
	headers[4] = NULL;
    }
    else
	headers[3] = NULL;

    /* Get general table info */
    strcpy(descbuf, "SELECT a.attname, t.typname, a.attlen, a.atttypmod, a.attnotnull, a.atthasdef, a.attnum");
    if (description)
	strcat(descbuf, ", obj_description(a.oid)");
    strcat(descbuf, "\nFROM pg_class c, pg_attribute a, pg_type t\n"
	   "WHERE c.relname = '");
    strncat(descbuf, name, NAMEDATALEN);
    strcat(descbuf, "'\n  AND a.attnum > 0 AND a.attrelid = c.oid AND a.atttypid = t.oid\n"
	   "ORDER BY a.attnum");

    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    /* Did we get anything? */
    if (PQntuples(res)==0) {
	if (!GetVariableBool(pset->vars, "quiet"))
	    fprintf(stdout, "Did not find any class named \"%s\".\n", name);
	PQclear(res);
	return false;
    }

    /* Check if table is a view */
    strcpy(descbuf, "SELECT definition FROM pg_views WHERE viewname = '");
    strncat(descbuf, name, NAMEDATALEN);
    strcat(descbuf, "'");
    res2 = PSQLexec(pset, descbuf);
    if (!res2)
	return false;

    if (PQntuples(res2) > 0)
	view_def = PQgetvalue(res2,0,0);



    /* Generate table cells to be printed */
    cells = calloc(PQntuples(res) * cols + 1, sizeof(*cells));
    if (!cells) {
	perror("calloc");
	exit(EXIT_FAILURE);
    }

    for (i = 0; i < PQntuples(res); i++) {
	int4 attypmod = atoi(PQgetvalue(res, i, 3));
	char * attype = PQgetvalue(res, i, 1);

	/* Name */
	cells[i*cols + 0] = PQgetvalue(res, i, 0); /* don't free this afterwards */

	/* Type */
	cells[i*cols + 1] = xmalloc(NAMEDATALEN + 16);
	if (strcmp(attype, "bpchar")==0)
	    sprintf(cells[i*cols + 1], "char(%d)", attypmod != -1 ? attypmod - VARHDRSZ : 0);
	else if (strcmp(attype, "varchar")==0)
	    sprintf(cells[i*cols + 1], "varchar(%d)", attypmod != -1 ? attypmod - VARHDRSZ : 0);
	else if (strcmp(attype, "numeric")==0)
	    sprintf(cells[i*cols + 1], "numeric(%d,%d)", ((attypmod - VARHDRSZ) >> 16) & 0xffff,
		    (attypmod - VARHDRSZ) & 0xffff );
	else if (attype[0] == '_')
	    sprintf(cells[i*cols + 1], "%s[]", attype+1);
	else
	    strcpy(cells[i*cols + 1], attype);

	/* Info */
	cells[i*cols + 2] = xmalloc(128 + 128); /* I'm cutting off the default string at 128 */
	cells[i*cols + 2][0] = '\0';
	if (strcmp(PQgetvalue(res, i, 4), "t") == 0)
	    strcat(cells[i*cols + 2], "not null");
	if (strcmp(PQgetvalue(res, i, 5), "t") == 0) {
	    /* handle "default" here */
	    strcpy(descbuf, "SELECT substring(d.adsrc for 128) FROM pg_attrdef d, pg_class c\n"
		            "WHERE c.relname = '");
	    strncat(descbuf, name, NAMEDATALEN);
	    strcat(descbuf, "' AND c.oid = d.adrelid AND d.adnum = ");
	    strcat(descbuf, PQgetvalue(res, i, 6));

	    res3 = PSQLexec(pset, descbuf);
	    if (!res) return false;
	    if (cells[i*cols+2][0]) strcat(cells[i*cols+2], " ");
	    strcat(cells[i*cols + 2], "default ");
	    strcat(cells[i*cols + 2], PQgetvalue(res3, 0, 0));
	}

	/* Description */
	if (description)
	    cells[i*cols + 3] = PQgetvalue(res, i, 7);
    }

    /* Make title */
    title = xmalloc(10 + strlen(name));
    if (view_def)
	sprintf(title, "View \"%s\"", name);
    else
	sprintf(title, "Table \"%s\"", name);

    /* Make footers */
    if (view_def) {
	footers = xmalloc(2 * sizeof(*footers));
	footers[0] = xmalloc(20 + strlen(view_def));
	sprintf(footers[0], "View definition: %s", view_def);
	footers[1] = NULL;
    }
    else {
	/* display indices */
	strcpy(descbuf, "SELECT c2.relname\n"
		        "FROM pg_class c, pg_class c2, pg_index i\n"
		        "WHERE c.relname = '");
	strncat(descbuf, name, NAMEDATALEN);
	strcat(descbuf, "' AND c.oid = i.indrelid AND i.indexrelid = c2.oid\n"
		        "ORDER BY c2.relname");
	res3 = PSQLexec(pset, descbuf);
	if (!res3)
	    return false;

	if (PQntuples(res3) > 0) {
	    footers = xmalloc((PQntuples(res3) + 1) * sizeof(*footers));

	    for (i=0; i<PQntuples(res3); i++) {
		footers[i] = xmalloc(10 + NAMEDATALEN);
		if (PQntuples(res3)==1)
		    sprintf(footers[i], "Index: %s", PQgetvalue(res3, i, 0));
		else if (i==0)
		    sprintf(footers[i], "Indices: %s", PQgetvalue(res3, i, 0));
		else
		    sprintf(footers[i], "         %s", PQgetvalue(res3, i, 0));
	    }

	    footers[i] = NULL;
	}
    }


    myopt.tuples_only = false;
    printTable(title, headers, cells, footers, "llll", &myopt, pset->queryFout);

    /* clean up */
    free(title);

    for (i = 0; i<PQntuples(res); i++) {
	free(cells[i*cols + 1]);
	free(cells[i*cols + 2]);
    }
    free(cells);

    for (ptr = footers; footers && *ptr; ptr++)
	free(*ptr);
    free(footers);

    PQclear(res);
    PQclear(res2);
    PQclear(res3);

    return true;
}



/*
 * listTables()
 *
 * handler for \d, \dt, etc.
 *
 * The infotype is an array of characters, specifying what info is desired:
 * t - tables
 * i - indices
 * v - views
 * s - sequences
 * S - systems tables (~'^pg_')
 * (any order of the above is fine)
 */
bool
listTables(const char * infotype, const char * name, PsqlSettings * pset)
{
    bool showTables = strchr(infotype, 't') != NULL;
    bool showIndices= strchr(infotype, 'i') != NULL;
    bool showViews  = strchr(infotype, 'v') != NULL;
    bool showSeq    = strchr(infotype, 's') != NULL;
    bool showSystem = strchr(infotype, 'S') != NULL;

    bool description = GetVariableBool(pset->vars, "description");

    char descbuf[1536 + 4 * REGEXP_CUTOFF];
    PGresult *res;
    printQueryOpt myopt = pset->popt;

    descbuf[0] = '\0';

    /* tables */
    if (showTables) {
	strcat(descbuf, "SELECT u.usename as \"Owner\", c.relname as \"Name\", 'table'::text as \"Type\"");
	if (description)
	    strcat(descbuf, ", obj_description(c.oid) as \"Description\"");
	strcat(descbuf, "\nFROM pg_class c, pg_user u\n"
	                "WHERE c.relowner = u.usesysid AND c.relkind = 'r'\n"
                        "  AND not exists (select 1 from pg_views where viewname = c.relname)\n");
	strcat(descbuf, showSystem ? "  AND c.relname ~ '^pg_'\n" : "  AND c.relname !~ '^pg_'\n");
	if (name) {
	    strcat(descbuf, "  AND c.relname ~ '^");
	    strncat(descbuf, name, REGEXP_CUTOFF);
	    strcat(descbuf, "'\n");
	}
    }

    /* views */
    if (showViews) {
	if (descbuf[0])
	    strcat(descbuf, "\nUNION\n\n");

	strcat(descbuf, "SELECT u.usename as \"Owner\", c.relname as \"Name\", 'view'::text as \"Type\"");
	if (description)
	    strcat(descbuf, ", obj_description(c.oid) as \"Description\"");
	strcat(descbuf, "\nFROM pg_class c, pg_user u\n"
	                "WHERE c.relowner = u.usesysid AND c.relkind = 'r'\n"
                        "  AND exists (select 1 from pg_views where viewname = c.relname)\n");
	strcat(descbuf, showSystem ? "  AND c.relname ~ '^pg_'\n" : "  AND c.relname !~ '^pg_'\n");
	if (name) {
	    strcat(descbuf, "  AND c.relname ~ '^");
	    strncat(descbuf, name, REGEXP_CUTOFF);
	    strcat(descbuf, "'\n");
	}
    }

    /* indices, sequences */
    if (showIndices || showSeq) {
	if (descbuf[0])
	    strcat(descbuf, "\nUNION\n\n");

	strcat(descbuf, "SELECT u.usename as \"Owner\", c.relname as \"Name\",\n"
	                "  (CASE WHEN relkind = 'S' THEN 'sequence'::text ELSE 'index'::text END) as \"Type\"");
	if (description)
	    strcat(descbuf, ", obj_description(c.oid) as \"Description\"");
	strcat(descbuf, "\nFROM pg_class c, pg_user u\n"
	                "WHERE c.relowner = u.usesysid AND relkind in (");
	if (showIndices && showSeq)
	    strcat(descbuf, "'i', 'S'");
	else if (showIndices)
	    strcat(descbuf, "'i'");
	else
	    strcat(descbuf, "'S'");
	strcat(descbuf, ")\n");

	/* ignore large-obj indices */
	if (showIndices)
	    strcat(descbuf, "  AND (c.relkind != 'i' OR c.relname !~ '^xinx')\n");

	strcat(descbuf, showSystem ? "  AND c.relname ~ '^pg_'\n" : "  AND c.relname !~ '^pg_'\n");
	if (name) {
	    strcat(descbuf, "  AND c.relname ~ '^");
	    strncat(descbuf, name, REGEXP_CUTOFF);
	    strcat(descbuf, "'\n");
	}
    }

    /* real system catalogue tables */
    if (showSystem && showTables) {
	if (descbuf[0])
	    strcat(descbuf, "\nUNION\n\n");

	strcat(descbuf, "SELECT u.usename as \"Owner\", c.relname as \"Name\", 'system'::text as \"Type\"");
	if (description)
	    strcat(descbuf, ", obj_description(c.oid) as \"Description\"");
	strcat(descbuf, "\nFROM pg_class c, pg_user u\n"
	                "WHERE c.relowner = u.usesysid AND c.relkind = 's'\n");
	if (name) {
	    strcat(descbuf, "  AND c.relname ~ '^");
	    strncat(descbuf, name, REGEXP_CUTOFF);
	    strcat(descbuf, "'\n");
	}
    }

    strcat(descbuf, "\nORDER BY \"Name\"");


    res = PSQLexec(pset, descbuf);
    if (!res)
	return false;

    if (PQntuples(res) == 0)
	fprintf(pset->queryFout, "No matching classes found.\n");

    else {
	myopt.topt.tuples_only = false;
	myopt.nullPrint = NULL;
	myopt.title = "List of classes";

	printQuery(res, &myopt, pset->queryFout);
    }

    PQclear(res);
    return true;
}


/* the end */