Add mixed affinity UPDATE, unify UUID behaviour

Makefile

@@ -15,7 +15,7 @@ OBJS = connection.o option.o deparse.o sqlite_query.o sqlite_fdw.o sqlite_data_n
 EXTENSION = sqlite_fdw
 DATA = sqlite_fdw--1.0.sql sqlite_fdw--1.0--1.1.sql
 
-REGRESS = extra/sqlite_fdw_post extra/float4 extra/float8 extra/int4 extra/int8 extra/numeric extra/join extra/limit extra/aggregates extra/prepare extra/select_having extra/select extra/insert extra/update extra/timestamp extra/encodings extra/bool extra/uuid sqlite_fdw type aggregate selectfunc 
+REGRESS = extra/sqlite_fdw_post extra/float4 extra/float8 extra/int4 extra/int8 extra/numeric extra/bitstring extra/bool extra/timestamp extra/uuid extra/join extra/limit extra/aggregates extra/prepare extra/select_having extra/select extra/insert extra/update extra/encodings sqlite_fdw type aggregate selectfunc 
 REGRESS_OPTS = --encoding=utf8
 
 SQLITE_LIB = sqlite3

README.md

@@ -227,7 +227,7 @@ In OS `sqlite_fdw` works as executed code with permissions of user of PostgreSQL
 in SQLite (mixed affinity case). Updated and inserted values will have this affinity. Default preferred SQLite affinity for `timestamp` and `uuid` PostgreSQL data types is `text`.
 
   - Use `INT` value for SQLite column (epoch Unix Time) to be treated/visualized as `timestamp` in PostgreSQL.
-  - Use `BLOB` value for SQLite column to be treated/visualized as `uuid` in PostgreSQL 14+.
+  - Use `BLOB` value for SQLite column to be treated/visualized as `uuid`.
 
 - **key** as *boolean*, optional, default *false*
 
@@ -542,7 +542,7 @@ Limitations
 ### UUID values
 - `sqlite_fdw` UUID values support exists only for `uuid` columns in foreign table. SQLite documentation recommends to store UUID as value with both `blob` and `text` [affinity](https://www.sqlite.org/datatype3.html). `sqlite_fdw` can pushdown both reading and filtering both `text` and `blob` values.
 - Expected affinity of UUID value in SQLite table determined by `column_type` option of the column
-for `INSERT` and `UPDATE` commands. In PostgreSQL 14- only `text` data affinity is availlable, PostgreSQL 14+ supports also `blob` data affinity.
+for `INSERT` and `UPDATE` commands. PostgreSQL supports both `blob` and `text` [affinity](https://www.sqlite.org/datatype3.html).
 
 ### bit and varbit support
 - `sqlite_fdw` PostgreSQL `bit`/`varbit` values support based on `int` SQLite data affinity, because there is no per bit operations for SQLite `blob` affinity data. Maximum SQLite `int` affinity value is 8 bytes length, hence maximum `bit`/`varbit` values length is 64 bits.
@@ -552,7 +552,7 @@ Tests
 -----
 Test directory have structure as following:
 
-```sql
+```
 +---sql
 |   +---12.16
 |   |       filename1.sql

deparse.c

@@ -164,6 +164,7 @@ static void sqlite_get_relation_column_alias_ids(Var *node, RelOptInfo *foreignr
 static char *sqlite_quote_identifier(const char *s, char q);
 static bool sqlite_contain_immutable_functions_walker(Node *node, void *context);
 static bool sqlite_is_valid_type(Oid type);
+int preferred_sqlite_affinity (Oid relid, int varattno);
 
 /*
  * Append remote name of specified foreign table to buf.
@@ -2107,6 +2108,9 @@ sqlite_deparse_column_ref(StringInfo buf, int varno, int varattno, PlannerInfo *
 	}
 }
 
+/*
+ * Get column option with optionname for a variable attribute in deparsing context
+ */
 static char *
 sqlite_deparse_column_option(int varno, int varattno, PlannerInfo *root, char *optionname)
 {
@@ -2296,6 +2300,35 @@ sqlite_deparse_update(StringInfo buf, PlannerInfo *root,
 	}
 }
 
+/* Preferred SQLite affinity from "column_type" foreign column option
+ * SQLITE_NULL if no value or no normal value
+ */
+int
+preferred_sqlite_affinity (Oid relid, int varattno)
+{
+	char	   *coltype = NULL;
+	List	   *options;
+	ListCell   *lc;
+
+	elog(DEBUG4, "sqlite_fdw : %s ", __func__);
+	if (varattno == 0)
+		return SQLITE_NULL;
+
+	options = GetForeignColumnOptions(relid, varattno);
+	foreach(lc, options)
+	{
+		DefElem	*def = (DefElem *) lfirst(lc);
+
+		if (strcmp(def->defname, "column_type") == 0)
+		{
+			coltype = defGetString(def);
+			break;
+		}
+		elog(DEBUG4, "column type = %s", coltype);
+	}
+	return sqlite_affinity_code(coltype);
+}
+
 /*
  * deparse remote UPDATE statement
  *
@@ -2346,7 +2379,11 @@ sqlite_deparse_direct_update_sql(StringInfo buf, PlannerInfo *root,
 	forboth(lc, targetlist, lc2, targetAttrs)
 	{
 		int			attnum = lfirst_int(lc2);
+		int			preferred_affinity = SQLITE_NULL;
 		TargetEntry *tle;
+		RangeTblEntry *rte;
+		bool		special_affinity = false;
+		Oid			pg_attyp;
 #if (PG_VERSION_NUM >= 140000)
 		tle = lfirst_node(TargetEntry, lc);
 
@@ -2366,8 +2403,27 @@ sqlite_deparse_direct_update_sql(StringInfo buf, PlannerInfo *root,
 		first = false;
 
 		sqlite_deparse_column_ref(buf, rtindex, attnum, root, false, true);
+
+		/* Get RangeTblEntry from array in PlannerInfo. */
+		rte = planner_rt_fetch(rtindex, root);
+		pg_attyp = get_atttype(rte->relid, attnum);
+		preferred_affinity = preferred_sqlite_affinity(rte->relid, attnum);
+
 		appendStringInfoString(buf, " = ");
+
+		special_affinity = (pg_attyp == UUIDOID && preferred_affinity == SQLITE3_TEXT) ||
+						   (pg_attyp == TIMESTAMPOID && preferred_affinity == SQLITE_INTEGER);
+		if (special_affinity)
+		{
+			elog(DEBUG3, "sqlite_fdw : aff %d\n", preferred_affinity);
+			if (pg_attyp == UUIDOID && preferred_affinity == SQLITE3_TEXT)
+				appendStringInfo(buf, "sqlite_fdw_uuid_str(");
+			if (pg_attyp == TIMESTAMPOID && preferred_affinity == SQLITE_INTEGER)
+				appendStringInfo(buf, "strftime(");
+		}
 		sqlite_deparse_expr((Expr *) tle->expr, &context);
+    	if (special_affinity)
+			appendStringInfoString(buf, ")");
 	}
 
 	sqlite_reset_transmission_modes(nestlevel);