Add exclusion constraints to analyze/read_schema (#658)

kvch · web-flow · commit c0dc02116ceb · 2025-02-05T17:04:34.000+01:00
This PR adds support for displaying exclusion constraints in the output
of `analyze`/`read_schema`.

Attributes:
* `name`: name of the constraint
* `method`: selected index method (`exclude.index_method` option)
* `columns`: the list of columns included in the constraint
* `predicate`: conditional expression if partials index
* `definition`: constraint definition

```
go run . analyze
{
...
  "excludeConstraints": {
    "forbid_duplicated_titles": {
      "name": "forbid_duplicated_titles",
      "method": "btree",
      "predicate": "(title IS NOT NULL)",
      "columns": [
        "title"
      ],
      "definition": "EXCLUDE USING btree (title WITH =) WHERE ((title IS NOT NULL))"
    }
  },
...
}
```

Furthermore, I added a new attribute called `exclusion` to indexes to
show if the index belongs to an exclusion constraint.
diff --git a/pkg/migrations/op_create_table.go b/pkg/migrations/op_create_table.go
@@ -244,10 +244,9 @@ func (o *OpCreateTable) updateSchema(s *schema.Schema) *schema.Schema {
 			}
 		case ConstraintTypeExclude:
 			excludeConstraints[c.Name] = &schema.ExcludeConstraint{
-				Name:        c.Name,
-				IndexMethod: c.Exclude.IndexMethod,
-				Elements:    c.Exclude.Elements,
-				Predicate:   c.Exclude.Predicate,
+				Name:      c.Name,
+				Method:    c.Exclude.IndexMethod,
+				Predicate: c.Exclude.Predicate,
 			}
 		}
 	}
diff --git a/pkg/schema/schema.go b/pkg/schema/schema.go
@@ -99,6 +99,9 @@ type Index struct {
 	// Unique indicates whether or not the index is unique
 	Unique bool `json:"unique"`
 
+	// Exclusion indicates whether or not the index is an exclusion index
+	Exclusion bool `json:"exclusion"`
+
 	// Columns is the set of key columns on which the index is defined
 	Columns []string `json:"columns"`
 
@@ -162,14 +165,17 @@ type ExcludeConstraint struct {
 	// Name is the name of the exclude constraint in postgres
 	Name string `json:"name"`
 
-	// IndexMethod is the index method of the exclude constraint
-	IndexMethod string `json:"indexMethod"`
-
-	// Elements is the elements of the exclude constraint
-	Elements string `json:"elements"`
+	// Method is the index method of the exclude constraint
+	Method string `json:"method"`
 
 	// Predicate is the predicate of the index
 	Predicate string `json:"predicate"`
+
+	// The columns that the exclusion constraint is defined on
+	Columns []string `json:"columns"`
+
+	// The definition of the exclusion
+	Definition string `json:"definition"`
 }
 
 // GetTable returns a table by name
diff --git a/pkg/state/init.sql b/pkg/state/init.sql
@@ -204,10 +204,10 @@ BEGIN
                                 AND pg_attribute.attnum = ANY (pg_index.indkey)
                                 AND indisprimary), 'indexes', (
                                 SELECT
-                                    COALESCE(json_object_agg(ix_details.name, json_build_object('name', ix_details.name, 'unique', ix_details.indisunique, 'columns', ix_details.columns, 'predicate', ix_details.predicate, 'method', ix_details.method, 'definition', ix_details.definition)), '{}'::json)
+                                    COALESCE(json_object_agg(ix_details.name, json_build_object('name', ix_details.name, 'unique', ix_details.indisunique, 'exclusion', ix_details.indisexclusion, 'columns', ix_details.columns, 'predicate', ix_details.predicate, 'method', ix_details.method, 'definition', ix_details.definition)), '{}'::json)
                             FROM (
                                 SELECT
-                                    replace(reverse(split_part(reverse(pi.indexrelid::regclass::text), '.', 1)), '"', '') AS name, pi.indisunique, array_agg(a.attname) AS columns, pg_get_expr(pi.indpred, t.oid) AS predicate, am.amname AS method, pg_get_indexdef(pi.indexrelid) AS definition
+                                    replace(reverse(split_part(reverse(pi.indexrelid::regclass::text), '.', 1)), '"', '') AS name, pi.indisunique, pi.indisexclusion, array_agg(a.attname) AS columns, pg_get_expr(pi.indpred, t.oid) AS predicate, am.amname AS method, pg_get_indexdef(pi.indexrelid) AS definition
                                 FROM pg_index pi
                                 JOIN pg_attribute a ON a.attrelid = pi.indrelid
                                     AND a.attnum = ANY (pi.indkey)
@@ -234,56 +234,69 @@ BEGIN
                                     AND uc_attr.attnum = ANY (uc_constraint.conkey)
                                 WHERE
                                     uc_constraint.conrelid = t.oid
-                                    AND uc_constraint.contype = 'u' GROUP BY uc_constraint.oid, uc_constraint.conname) AS uc_details), 'foreignKeys', (
+                                    AND uc_constraint.contype = 'u' GROUP BY uc_constraint.oid, uc_constraint.conname) AS uc_details), 'excludeConstraints', (
                                 SELECT
-                                    COALESCE(json_object_agg(fk_details.conname, json_build_object('name', fk_details.conname, 'columns', fk_details.columns, 'referencedTable', fk_details.referencedTable, 'referencedColumns', fk_details.referencedColumns, 'matchType', fk_details.matchType, 'onDelete', fk_details.onDelete, 'onUpdate', fk_details.onUpdate)), '{}'::json)
+                                    COALESCE(json_object_agg(xc_details.conname, json_build_object('name', xc_details.conname, 'columns', xc_details.columns, 'definition', xc_details.definition, 'predicate', xc_details.predicate, 'method', xc_details.method)), '{}'::json)
                                 FROM (
                                     SELECT
-                                        fk_info.conname AS conname, fk_info.columns AS columns, fk_info.relname AS referencedTable, array_agg(ref_attr.attname ORDER BY ref_attr.attname) AS referencedColumns, CASE WHEN fk_info.confmatchtype = 'f' THEN
-                                        'FULL'
-                                    WHEN fk_info.confmatchtype = 'p' THEN
-                                        'PARTIAL'
-                                    WHEN fk_info.confmatchtype = 's' THEN
-                                        'SIMPLE'
-                                    END AS matchType, CASE WHEN fk_info.confdeltype = 'a' THEN
-                                        'NO ACTION'
-                                    WHEN fk_info.confdeltype = 'r' THEN
-                                        'RESTRICT'
-                                    WHEN fk_info.confdeltype = 'c' THEN
-                                        'CASCADE'
-                                    WHEN fk_info.confdeltype = 'd' THEN
-                                        'SET DEFAULT'
-                                    WHEN fk_info.confdeltype = 'n' THEN
-                                        'SET NULL'
-                                    END AS onDelete, CASE WHEN fk_info.confupdtype = 'a' THEN
-                                        'NO ACTION'
-                                    WHEN fk_info.confupdtype = 'r' THEN
-                                        'RESTRICT'
-                                    WHEN fk_info.confupdtype = 'c' THEN
-                                        'CASCADE'
-                                    WHEN fk_info.confupdtype = 'd' THEN
-                                        'SET DEFAULT'
-                                    WHEN fk_info.confupdtype = 'n' THEN
-                                        'SET NULL'
-                                    END AS onUpdate FROM (
+                                        xc_constraint.conname, array_agg(xc_attr.attname ORDER BY xc_constraint.conkey::int[]) AS columns, pg_get_expr(pi.indpred, t.oid) AS predicate, am.amname AS method, pg_get_constraintdef(xc_constraint.oid) AS definition FROM pg_constraint AS xc_constraint
+                                    INNER JOIN pg_attribute xc_attr ON xc_attr.attrelid = xc_constraint.conrelid
+                                        AND xc_attr.attnum = ANY (xc_constraint.conkey)
+                                    JOIN pg_index pi ON pi.indexrelid = xc_constraint.conindid
+                                    JOIN pg_class cls ON cls.oid = pi.indexrelid
+                                    JOIN pg_am am ON am.oid = cls.relam
+                                    WHERE
+                                        xc_constraint.conrelid = t.oid
+                                        AND xc_constraint.contype = 'x' GROUP BY xc_constraint.oid, xc_constraint.conname, pi.indpred, pi.indexrelid, am.amname) AS xc_details), 'foreignKeys', (
+                                    SELECT
+                                        COALESCE(json_object_agg(fk_details.conname, json_build_object('name', fk_details.conname, 'columns', fk_details.columns, 'referencedTable', fk_details.referencedTable, 'referencedColumns', fk_details.referencedColumns, 'matchType', fk_details.matchType, 'onDelete', fk_details.onDelete, 'onUpdate', fk_details.onUpdate)), '{}'::json)
+                                    FROM (
                                         SELECT
-                                            fk_constraint.conname, fk_constraint.conrelid, fk_constraint.confrelid, fk_constraint.confkey, fk_cl.relname, fk_constraint.confmatchtype, fk_constraint.confdeltype, fk_constraint.confupdtype, array_agg(fk_attr.attname ORDER BY fk_attr.attname) AS columns FROM pg_constraint AS fk_constraint
-                                        INNER JOIN pg_class fk_cl ON fk_constraint.confrelid = fk_cl.oid -- join the referenced table
-                                        INNER JOIN pg_attribute fk_attr ON fk_attr.attrelid = fk_constraint.conrelid
-                                            AND fk_attr.attnum = ANY (fk_constraint.conkey) -- join the columns of the referencing table
-                                        WHERE
-                                            fk_constraint.conrelid = t.oid
-                                            AND fk_constraint.contype = 'f' GROUP BY fk_constraint.conrelid, fk_constraint.conname, fk_constraint.confrelid, fk_cl.relname, fk_constraint.confkey, fk_constraint.confmatchtype, fk_constraint.confdeltype, fk_constraint.confupdtype) AS fk_info
-                                        INNER JOIN pg_attribute ref_attr ON ref_attr.attrelid = fk_info.confrelid
-                                            AND ref_attr.attnum = ANY (fk_info.confkey) -- join the columns of the referenced table
-                                    GROUP BY fk_info.conname, fk_info.conrelid, fk_info.columns, fk_info.confrelid, fk_info.confmatchtype, fk_info.confdeltype, fk_info.confupdtype, fk_info.relname) AS fk_details))), '{}'::json)
-                    FROM pg_class AS t
-                    INNER JOIN pg_namespace AS ns ON t.relnamespace = ns.oid
-                    LEFT JOIN pg_description AS descr ON t.oid = descr.objoid
-                        AND descr.objsubid = 0
-                    WHERE
-                        ns.nspname = schemaname
-                        AND t.relkind IN ('r', 'p') -- tables only (ignores views, materialized views & foreign tables)
+                                            fk_info.conname AS conname, fk_info.columns AS columns, fk_info.relname AS referencedTable, array_agg(ref_attr.attname ORDER BY ref_attr.attname) AS referencedColumns, CASE WHEN fk_info.confmatchtype = 'f' THEN
+                                            'FULL'
+                                        WHEN fk_info.confmatchtype = 'p' THEN
+                                            'PARTIAL'
+                                        WHEN fk_info.confmatchtype = 's' THEN
+                                            'SIMPLE'
+                                        END AS matchType, CASE WHEN fk_info.confdeltype = 'a' THEN
+                                            'NO ACTION'
+                                        WHEN fk_info.confdeltype = 'r' THEN
+                                            'RESTRICT'
+                                        WHEN fk_info.confdeltype = 'c' THEN
+                                            'CASCADE'
+                                        WHEN fk_info.confdeltype = 'd' THEN
+                                            'SET DEFAULT'
+                                        WHEN fk_info.confdeltype = 'n' THEN
+                                            'SET NULL'
+                                        END AS onDelete, CASE WHEN fk_info.confupdtype = 'a' THEN
+                                            'NO ACTION'
+                                        WHEN fk_info.confupdtype = 'r' THEN
+                                            'RESTRICT'
+                                        WHEN fk_info.confupdtype = 'c' THEN
+                                            'CASCADE'
+                                        WHEN fk_info.confupdtype = 'd' THEN
+                                            'SET DEFAULT'
+                                        WHEN fk_info.confupdtype = 'n' THEN
+                                            'SET NULL'
+                                        END AS onUpdate FROM (
+                                            SELECT
+                                                fk_constraint.conname, fk_constraint.conrelid, fk_constraint.confrelid, fk_constraint.confkey, fk_cl.relname, fk_constraint.confmatchtype, fk_constraint.confdeltype, fk_constraint.confupdtype, array_agg(fk_attr.attname ORDER BY fk_attr.attname) AS columns FROM pg_constraint AS fk_constraint
+                                            INNER JOIN pg_class fk_cl ON fk_constraint.confrelid = fk_cl.oid -- join the referenced table
+                                            INNER JOIN pg_attribute fk_attr ON fk_attr.attrelid = fk_constraint.conrelid
+                                                AND fk_attr.attnum = ANY (fk_constraint.conkey) -- join the columns of the referencing table
+                                            WHERE
+                                                fk_constraint.conrelid = t.oid
+                                                AND fk_constraint.contype = 'f' GROUP BY fk_constraint.conrelid, fk_constraint.conname, fk_constraint.confrelid, fk_cl.relname, fk_constraint.confkey, fk_constraint.confmatchtype, fk_constraint.confdeltype, fk_constraint.confupdtype) AS fk_info
+                                            INNER JOIN pg_attribute ref_attr ON ref_attr.attrelid = fk_info.confrelid
+                                                AND ref_attr.attnum = ANY (fk_info.confkey) -- join the columns of the referenced table
+                                        GROUP BY fk_info.conname, fk_info.conrelid, fk_info.columns, fk_info.confrelid, fk_info.confmatchtype, fk_info.confdeltype, fk_info.confupdtype, fk_info.relname) AS fk_details))), '{}'::json)
+                        FROM pg_class AS t
+                        INNER JOIN pg_namespace AS ns ON t.relnamespace = ns.oid
+                        LEFT JOIN pg_description AS descr ON t.oid = descr.objoid
+                            AND descr.objsubid = 0
+                        WHERE
+                            ns.nspname = schemaname
+                            AND t.relkind IN ('r', 'p') -- tables only (ignores views, materialized views & foreign tables)
 )) INTO tables;
     RETURN tables;
 END;
diff --git a/pkg/state/state_test.go b/pkg/state/state_test.go

Original file line number	Diff line number	Diff line change
`@@ -244,10 +244,9 @@ func (o OpCreateTable) updateSchema(s schema.Schema) *schema.Schema {`
`244`	`244`	`}`
`245`	`245`	`case ConstraintTypeExclude:`
`246`	`246`	`excludeConstraints[c.Name] = &schema.ExcludeConstraint{`
`247`		`- Name: c.Name,`
`248`		`- IndexMethod: c.Exclude.IndexMethod,`
`249`		`- Elements: c.Exclude.Elements,`
`250`		`- Predicate: c.Exclude.Predicate,`
	`247`	`+ Name: c.Name,`
	`248`	`+ Method: c.Exclude.IndexMethod,`
	`249`	`+ Predicate: c.Exclude.Predicate,`
`251`	`250`	`}`
`252`	`251`	`}`
`253`	`252`	`}`