Clean db indexes

- Swap wrong index names `history_decoded_not_proc_idx` and `history_decoded_processed_idx`
- Remove not used indexes

The following indexes have been identified as unused (0 scans) and are being removed to reduce database size:

| Index Name | Mainnet DB Size | Polygon DB Size | Usage Status | Justification |
|------------|----------------|-----------------|--------------|---------------|
| `history_ethereumtx_to_9fb37c13` | 1588 MB | 9893 MB | 0 scans | Unused - no queries filter by `to` field |
| `history_ethereumtx__from_e36d4662` | 1758 MB | 8707 MB | 0 scans | Unused - no queries filter by `_from` field |
| `history_ethereumtx_status_d1d0de2c` | 1074 MB | 6645 MB | 0 scans | Unused - no queries filter by `status` field |
| `history_internaltxdecoded_function_name_333ae03e` | 519 MB | 3204 MB | 0 scans (DB1) / 69K scans (DB2) | Replaced by dedicated `history_decoded_setup_idx` for `function_name="setup"` queries |
| `history_internaltxdecoded_function_name_333ae03e_like` | 519 MB | 3205 MB | 0 scans | Unused - no LIKE queries on `function_name` |
| `history_multisigtransaction_failed_4842ad6b` | 43 MB | N/A | 0 scans | Unused - field is used but index is not needed |
| `history_decoded_setup_idx` | 13 MB | 194 MB | 0 scans (DB1) / 62K scans (DB2) | **KEEPING** - Used in DB2, will monitor DB1 |
| `history_safe_banned_idx` | 8 KB | N/A | 0 scans | Unused - no queries filter by `banned=True` |

**Total Potential Savings:**
- Database 1: ~5.5 GB
- Database 2: ~28.5 GB

**Note:** The `function_name` indexes are being removed because:
- The dedicated `history_decoded_setup_idx` (partial index on `safe_address` WHERE `function_name="setup"`) covers the only production query that filters by `function_name`
- Admin interface filtering does not require these indexes for performance
- All other `function_name` queries are in tests or already-executed migrations

Author: Uxio0

safe_transaction_service/history/migrations/0099_alter_ethereumtx__from_alter_ethereumtx_status_and_more.py

@@ -0,0 +1,52 @@
+# Generated by Django 5.2.9 on 2025-12-10 13:18
+
+import safe_eth.eth.django.models
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('history', '0098_internaltxdecoded_setup_idx'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='ethereumtx',
+            name='_from',
+            field=safe_eth.eth.django.models.EthereumAddressBinaryField(null=True),
+        ),
+        migrations.AlterField(
+            model_name='ethereumtx',
+            name='status',
+            field=models.IntegerField(default=None, null=True),
+        ),
+        migrations.AlterField(
+            model_name='ethereumtx',
+            name='to',
+            field=safe_eth.eth.django.models.EthereumAddressBinaryField(null=True),
+        ),
+        migrations.AlterField(
+            model_name='internaltxdecoded',
+            name='function_name',
+            field=models.CharField(max_length=256),
+        ),
+        # Fix index naming: swap the names to match their conditions
+        # history_decoded_processed_idx has processed=False (should be "not_proc")
+        # history_decoded_not_proc_idx has processed=True (should be "processed")
+        migrations.RenameIndex(
+            model_name='internaltxdecoded',
+            old_name='history_decoded_processed_idx',
+            new_name='history_decoded_not_proc_idx_temp',
+        ),
+        migrations.RenameIndex(
+            model_name='internaltxdecoded',
+            old_name='history_decoded_not_proc_idx',
+            new_name='history_decoded_processed_idx',
+        ),
+        migrations.RenameIndex(
+            model_name='internaltxdecoded',
+            old_name='history_decoded_not_proc_idx_temp',
+            new_name='history_decoded_not_proc_idx',
+        ),
+    ]

safe_transaction_service/history/models.py

@@ -428,18 +428,18 @@ class EthereumTx(TimeStampedModel):
     tx_hash = Keccak256Field(primary_key=True)
     gas_used = Uint256Field(null=True, default=None)  # If mined
     status = models.IntegerField(
-        null=True, default=None, db_index=True
+        null=True, default=None
     )  # If mined. Old txs don't have `status`
     logs = ArrayField(JSONField(), null=True, default=None)  # If mined
     transaction_index = models.PositiveIntegerField(null=True, default=None)  # If mined
-    _from = EthereumAddressBinaryField(null=True, db_index=True)
+    _from = EthereumAddressBinaryField(null=True)
     gas = Uint256Field()
     gas_price = Uint256Field()
     max_fee_per_gas = Uint256Field(null=True, blank=True, default=None)
     max_priority_fee_per_gas = Uint256Field(null=True, blank=True, default=None)
     data = models.BinaryField(null=True)
     nonce = Uint256Field()
-    to = EthereumAddressBinaryField(null=True, db_index=True)
+    to = EthereumAddressBinaryField(null=True)
     value = Uint256Field()
     type = models.PositiveSmallIntegerField(default=0)
 
@@ -1360,7 +1360,7 @@ class InternalTxDecoded(models.Model):
         related_name="decoded_tx",
         primary_key=True,
     )
-    function_name = models.CharField(max_length=256, db_index=True)
+    function_name = models.CharField(max_length=256)
     arguments = JSONField()
     processed = models.BooleanField(default=False)
     # Denormalized from internal_tx._from for efficient querying
@@ -1370,12 +1370,12 @@ class InternalTxDecoded(models.Model):
     class Meta:
         indexes = [
             models.Index(
-                name="history_decoded_processed_idx",
+                name="history_decoded_not_proc_idx",
                 fields=["internal_tx_id"],
                 condition=Q(processed=False),
             ),
             models.Index(
-                name="history_decoded_not_proc_idx",
+                name="history_decoded_processed_idx",
                 fields=["internal_tx_id"],
                 condition=Q(processed=True),  # For finding out of order transactions
             ),