fix: capture index schema at open time, gate ops on feature, surface raw-SQL hints

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/lib/components/DBIndexManager.svelte

@@ -30,6 +30,7 @@
 	}
 	let { dbIndexOps, tableKey, schema, availableColumns }: Props = $props()
 
+	// Keep in sync with PG_INDEX_METHODS in backend/windmill-common/src/query_builders.rs
 	const INDEX_METHODS = ['btree', 'hash', 'gin', 'gist', 'brin', 'spgist']
 
 	let indexes = resource(
@@ -140,11 +141,12 @@
 		confirm.loading = true
 		try {
 			await confirm.onConfirm()
-			confirm = undefined
 		} catch (e) {
 			toastErr(e)
-			if (confirm) confirm.loading = false
+			confirm.loading = false
+			return
 		}
+		confirm = undefined
 	}
 </script>
 
@@ -264,7 +266,11 @@
 						<Toggle
 							size="xs"
 							bind:checked={column.isExpression}
-							options={{ right: 'expr', rightTooltip: 'Use a raw SQL expression' }}
+							options={{
+								right: 'expr',
+								rightTooltip:
+									'Treat the value as a raw SQL expression (e.g. lower(email)) — inserted verbatim, not escaped'
+							}}
 						/>
 						<Button
 							color="light"
@@ -318,7 +324,10 @@
 		/>
 		{#if showAdvanced}
 			<div class="flex flex-col gap-3 border-l-2 border-surface-selected pl-3">
-				<Label label="Partial index predicate (WHERE)">
+				<Label
+					label="Partial index predicate (WHERE)"
+					tooltip="Raw SQL inserted verbatim after WHERE — not escaped"
+				>
 					<TextInput
 						bind:value={form.where}
 						inputProps={{ type: 'text', placeholder: 'active = true' }}

frontend/src/lib/components/DBManager.svelte

@@ -236,7 +236,9 @@
 		}
 	)
 
-	let dbIndexManagerState: { open: boolean; tableKey?: string } = $state({ open: false })
+	let dbIndexManagerState: { open: boolean; tableKey?: string; schemaKey?: string } = $state({
+		open: false
+	})
 
 	let newSchemaDialogOpen = $state(false)
 	let newSchemaName = $state('')
@@ -526,7 +528,11 @@
 												displayName: 'Manage indexes',
 												icon: ListTree,
 												action: () => {
-													dbIndexManagerState = { open: true, tableKey }
+													dbIndexManagerState = {
+														open: true,
+														tableKey,
+														schemaKey: selected.schemaKey
+													}
 												}
 											}
 										]
@@ -684,12 +690,13 @@
 	>
 		{#if dbIndexManagerState.tableKey && dbIndexOps}
 			{@const indexTableKey = dbIndexManagerState.tableKey}
+			{@const indexSchemaKey = dbIndexManagerState.schemaKey}
 			<DBIndexManager
 				{dbIndexOps}
 				tableKey={indexTableKey}
-				schema={selected.schemaKey}
+				schema={indexSchemaKey}
 				availableColumns={Object.keys(
-					dbSchema?.schema?.[selected.schemaKey ?? '']?.[indexTableKey] ?? {}
+					dbSchema?.schema?.[indexSchemaKey ?? '']?.[indexTableKey] ?? {}
 				)}
 			/>
 		{/if}

frontend/src/lib/components/DBManagerContent.svelte

@@ -166,10 +166,9 @@
 					input: _input,
 					workspace: $workspaceStore
 				})}
-				dbIndexOps={dbIndexOpsWithPreviewScripts({
-					input: _input,
-					workspace: $workspaceStore
-				})}
+				dbIndexOps={getDbFeatures(_input).indexes
+					? dbIndexOpsWithPreviewScripts({ input: _input, workspace: $workspaceStore })
+					: undefined}
 				initialTableKey={input.specificTable}
 				initialSchemaKey={input.type == 'database' ? input.specificSchema : undefined}
 				asset={_input.type == 'ducklake'