Re: [PATCH] Tab completion for ALTER TABLE … ADD … - Mailing list pgsql-hackers

Michael Paquier <michael@paquier.xyz> writes:

> On Tue, Aug 03, 2021 at 12:48:38PM +0100, Dagfinn Ilmari Mannsåker wrote:
>> The other day I noticed that there's no tab completion after ALTER TABLE
>> … ADD, so here's a patch.  In addition to COLUMN and all the table
>> constraint types, it also completes with the list of unique indexes on
>> the table after ALTER TABLE … ADD … USING INDEX.
>
> I was reading this patch (not actually tested), and that's a clear
> improvement.  One extra thing that could be done here is to complete
> with types for a ALTER TABLE ADD COLUMN foo.

That was easy enough to add (just a bit of extra fiddling to handle
COLUMN being optional), done in the attached v2 patch.

> We could as well have a list of columns after UNIQUE or PRIMARY KEY,
> but that feels like extra cream on top of the cake.

Doing a list of arbitrarily many comma-separated names is more
complicated, so that can be the subject for another patch.

>  In short I am fine with what you have here.

Thanks for the review.

- ilmari

From 0bdf91f2a66bf9393e6900db904bda1961c03350 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Tue, 3 Aug 2021 12:23:07 +0100
Subject: [PATCH v2] =?UTF-8?q?Add=20tab=20completion=20for=20ALTER=20TABLE?=
 =?UTF-8?q?=20=E2=80=A6=20ADD=20=E2=80=A6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Complete with COLUMN plus the various table constraint types, list
unique indexes on the table after ADD (UNQIUE|PRIMARY KEY) USING INDEX,
and data types after ADD [COLUMN] <column_name>.
---
 src/bin/psql/tab-complete.c | 49 +++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index 7cdfc7c637..bb7c3fc5cf 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -776,6 +776,10 @@ static const SchemaQuery Query_for_list_of_collations = {
 "       and pg_catalog.quote_ident(c1.relname)='%s'"\
 "       and pg_catalog.pg_table_is_visible(c2.oid)"
 
+#define Query_for_unique_index_of_table \
+Query_for_index_of_table \
+"       and i.indisunique"
+
 /* the silly-looking length condition is just to eat up the current word */
 #define Query_for_constraint_of_table \
 "SELECT pg_catalog.quote_ident(conname) "\
@@ -2019,6 +2023,51 @@ psql_completion(const char *text, int start, int end)
                       "OWNER TO", "SET", "VALIDATE CONSTRAINT",
                       "REPLICA IDENTITY", "ATTACH PARTITION",
                       "DETACH PARTITION", "FORCE ROW LEVEL SECURITY");
+    /* ALTER TABLE xxx ADD */
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD"))
+        COMPLETE_WITH("COLUMN", "CONSTRAINT", "CHECK", "UNIQUE", "PRIMARY KEY",
+                      "EXCLUDE", "FOREIGN KEY");
+    /* ALTER TABLE xxx ADD CONSTRAINT yyy */
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny))
+        COMPLETE_WITH("CHECK", "UNIQUE", "PRIMARY KEY", "EXCLUDE", "FOREIGN KEY");
+    /* ALTER TABLE xxx ADD (CONSTRAINT yyy)? FOREIGN|PRIMARY */
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "FOREIGN|PRIMARY") ||
+             Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny, "FOREIGN|PRIMARY"))
+        COMPLETE_WITH("KEY");
+    /* ALTER TABLE xxx ADD (CONSTRAINT yyy)? (PRIMARY KEY|UNIQUE) */
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "PRIMARY", "KEY") ||
+             Matches("ALTER", "TABLE", MatchAny, "ADD", "UNIQUE") ||
+             Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny, "PRIMARY", "KEY") ||
+             Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny, "UNIQUE"))
+        COMPLETE_WITH("(", "USING INDEX");
+    /* ALTER TABLE xxx ADD (CONSTRAINT yyy)? ... USING INDEX */
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "PRIMARY", "KEY", "USING", "INDEX"))
+    {
+        completion_info_charp = prev6_wd;
+        COMPLETE_WITH_QUERY(Query_for_unique_index_of_table);
+    }
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "UNIQUE", "USING", "INDEX"))
+    {
+        completion_info_charp = prev5_wd;
+        COMPLETE_WITH_QUERY(Query_for_unique_index_of_table);
+    }
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny,
+                     "PRIMARY", "KEY", "USING", "INDEX"))
+    {
+        completion_info_charp = prev8_wd;
+        COMPLETE_WITH_QUERY(Query_for_unique_index_of_table);
+    }
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny,
+                     "UNIQUE", "USING", "INDEX"))
+    {
+        completion_info_charp = prev7_wd;
+        COMPLETE_WITH_QUERY(Query_for_unique_index_of_table);
+    }
+    /* ADD column_name must be last of the ALTER TABLE xxx ADD matches */
+    else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "COLUMN", MatchAny) ||
+             (Matches("ALTER", "TABLE", MatchAny, "ADD", MatchAny) &&
+              !Matches("ALTER", "TABLE", MatchAny, "ADD", "COLUMN")))
+        COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_datatypes, NULL);
     /* ALTER TABLE xxx ENABLE */
     else if (Matches("ALTER", "TABLE", MatchAny, "ENABLE"))
         COMPLETE_WITH("ALWAYS", "REPLICA", "ROW LEVEL SECURITY", "RULE",
-- 
2.30.2