diff --git a/crates/tranquil-db-traits/src/error.rs b/crates/tranquil-db-traits/src/error.rs
index 43add05..547a110 100644
--- a/crates/tranquil-db-traits/src/error.rs
+++ b/crates/tranquil-db-traits/src/error.rs
@@ -1,5 +1,31 @@
 use thiserror::Error;
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct ColumnRef {
+    table: &'static str,
+    column: &'static str,
+}
+
+impl ColumnRef {
+    pub const fn new(table: &'static str, column: &'static str) -> Self {
+        Self { table, column }
+    }
+
+    pub const fn table(&self) -> &'static str {
+        self.table
+    }
+
+    pub const fn column(&self) -> &'static str {
+        self.column
+    }
+}
+
+impl std::fmt::Display for ColumnRef {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}.{}", self.table, self.column)
+    }
+}
+
 #[derive(Debug, Error)]
 pub enum DbError {
     #[error("Database query error: {0}")]
@@ -29,6 +55,9 @@ pub enum DbError {
     #[error("Corrupt data in column: {0}")]
     CorruptData(&'static str),
 
+    #[error("Column {0} has a value that isn't valid for its type")]
+    InvalidColumn(ColumnRef),
+
     #[error("Other database error: {0}")]
     Other(String),
 }
diff --git a/crates/tranquil-db-traits/src/lib.rs b/crates/tranquil-db-traits/src/lib.rs
index c628930..b71a3eb 100644
--- a/crates/tranquil-db-traits/src/lib.rs
+++ b/crates/tranquil-db-traits/src/lib.rs
@@ -20,7 +20,7 @@ pub use delegation::{
     AuditLogEntry, ControllerInfo, DelegatedAccountInfo, DelegationActionType, DelegationGrant,
     DelegationRepository,
 };
-pub use error::DbError;
+pub use error::{ColumnRef, DbError};
 pub use infra::{
     AdminAccountInfo, CommsChannel, CommsStatus, CommsType, DeletionRequest,
     DeletionRequestWithToken, InfraRepository, InviteCodeInfo, InviteCodeRow, InviteCodeSortOrder,
diff --git a/crates/tranquil-db/src/postgres/mod.rs b/crates/tranquil-db/src/postgres/mod.rs
index a05da3a..1f97998 100644
--- a/crates/tranquil-db/src/postgres/mod.rs
+++ b/crates/tranquil-db/src/postgres/mod.rs
@@ -10,7 +10,106 @@ mod sso;
 mod user;
 
 use sqlx::PgPool;
+use std::str::FromStr;
 use std::sync::Arc;
+use tranquil_db_traits::{ColumnRef, DbError};
+
+pub(crate) mod col {
+    use tranquil_db_traits::ColumnRef;
+
+    pub const ACCOUNT_DELEGATIONS_CONTROLLER_DID: ColumnRef =
+        ColumnRef::new("account_delegations", "controller_did");
+    pub const ACCOUNT_DELEGATIONS_DELEGATED_DID: ColumnRef =
+        ColumnRef::new("account_delegations", "delegated_did");
+    pub const ACCOUNT_DELEGATIONS_GRANTED_BY: ColumnRef =
+        ColumnRef::new("account_delegations", "granted_by");
+    pub const ACCOUNT_DELEGATIONS_REVOKED_BY: ColumnRef =
+        ColumnRef::new("account_delegations", "revoked_by");
+    pub const ACCOUNT_DELETION_REQUESTS_DID: ColumnRef =
+        ColumnRef::new("account_deletion_requests", "did");
+    pub const APP_PASSWORDS_CREATED_BY_CONTROLLER_DID: ColumnRef =
+        ColumnRef::new("app_passwords", "created_by_controller_did");
+    pub const BACKLINKS_URI: ColumnRef = ColumnRef::new("backlinks", "uri");
+    pub const BLOBS_CID: ColumnRef = ColumnRef::new("blobs", "cid");
+    pub const DELEGATION_AUDIT_LOG_ACTOR_DID: ColumnRef =
+        ColumnRef::new("delegation_audit_log", "actor_did");
+    pub const DELEGATION_AUDIT_LOG_CONTROLLER_DID: ColumnRef =
+        ColumnRef::new("delegation_audit_log", "controller_did");
+    pub const DELEGATION_AUDIT_LOG_DELEGATED_DID: ColumnRef =
+        ColumnRef::new("delegation_audit_log", "delegated_did");
+    pub const INVITE_CODES_FOR_ACCOUNT: ColumnRef = ColumnRef::new("invite_codes", "for_account");
+    pub const OAUTH_2FA_CHALLENGE_DID: ColumnRef = ColumnRef::new("oauth_2fa_challenge", "did");
+    pub const OAUTH_AUTHORIZATION_REQUEST_CONTROLLER_DID: ColumnRef =
+        ColumnRef::new("oauth_authorization_request", "controller_did");
+    pub const OAUTH_AUTHORIZATION_REQUEST_DID: ColumnRef =
+        ColumnRef::new("oauth_authorization_request", "did");
+    pub const OAUTH_TOKEN_CONTROLLER_DID: ColumnRef =
+        ColumnRef::new("oauth_token", "controller_did");
+    pub const OAUTH_TOKEN_DID: ColumnRef = ColumnRef::new("oauth_token", "did");
+    pub const PASSKEYS_DID: ColumnRef = ColumnRef::new("passkeys", "did");
+    pub const RECORD_BLOBS_BLOB_CID: ColumnRef = ColumnRef::new("record_blobs", "blob_cid");
+    pub const RECORD_BLOBS_RECORD_URI: ColumnRef = ColumnRef::new("record_blobs", "record_uri");
+    pub const RECORDS_COLLECTION: ColumnRef = ColumnRef::new("records", "collection");
+    pub const RECORDS_RECORD_CID: ColumnRef = ColumnRef::new("records", "record_cid");
+    pub const RECORDS_RKEY: ColumnRef = ColumnRef::new("records", "rkey");
+    pub const REPO_SEQ_BLOBS: ColumnRef = ColumnRef::new("repo_seq", "blobs");
+    pub const REPO_SEQ_BLOCKS_CIDS: ColumnRef = ColumnRef::new("repo_seq", "blocks_cids");
+    pub const REPO_SEQ_COMMIT_CID: ColumnRef = ColumnRef::new("repo_seq", "commit_cid");
+    pub const REPO_SEQ_DID: ColumnRef = ColumnRef::new("repo_seq", "did");
+    pub const REPO_SEQ_HANDLE: ColumnRef = ColumnRef::new("repo_seq", "handle");
+    pub const REPO_SEQ_PREV_CID: ColumnRef = ColumnRef::new("repo_seq", "prev_cid");
+    pub const REPO_SEQ_PREV_DATA_CID: ColumnRef = ColumnRef::new("repo_seq", "prev_data_cid");
+    pub const REPO_SEQ_REV: ColumnRef = ColumnRef::new("repo_seq", "rev");
+    pub const REPOS_REPO_REV: ColumnRef = ColumnRef::new("repos", "repo_rev");
+    pub const REPOS_REPO_ROOT_CID: ColumnRef = ColumnRef::new("repos", "repo_root_cid");
+    pub const RESERVED_SIGNING_KEYS_DID: ColumnRef = ColumnRef::new("reserved_signing_keys", "did");
+    pub const RESERVED_SIGNING_KEYS_PUBLIC_KEY_DID_KEY: ColumnRef =
+        ColumnRef::new("reserved_signing_keys", "public_key_did_key");
+    pub const SESSION_TOKENS_CONTROLLER_DID: ColumnRef =
+        ColumnRef::new("session_tokens", "controller_did");
+    pub const SESSION_TOKENS_DID: ColumnRef = ColumnRef::new("session_tokens", "did");
+    pub const USERS_DID: ColumnRef = ColumnRef::new("users", "did");
+    pub const USERS_HANDLE: ColumnRef = ColumnRef::new("users", "handle");
+}
+
+pub(crate) fn column<T: FromStr>(value: String, name: ColumnRef) -> Result<T, DbError> {
+    T::from_str(&value).map_err(|_| {
+        tracing::error!(
+            column = %name,
+            value = %value,
+            "column has a value that isn't valid for its type"
+        );
+        DbError::InvalidColumn(name)
+    })
+}
+
+pub(crate) fn opt_column<T: FromStr>(
+    value: Option<String>,
+    name: ColumnRef,
+) -> Result<Option<T>, DbError> {
+    value.map(|v| column(v, name)).transpose()
+}
+
+pub(crate) fn legacy_column<T: FromStr>(value: String, name: ColumnRef) -> Option<T> {
+    match T::from_str(&value) {
+        Ok(v) => Some(v),
+        Err(_) => {
+            tracing::warn!(
+                column = %name,
+                value = %value,
+                "ignoring a column value that isn't valid for its type"
+            );
+            None
+        }
+    }
+}
+
+pub(crate) fn column_vec<T: FromStr>(
+    values: Vec<String>,
+    name: ColumnRef,
+) -> Result<Vec<T>, DbError> {
+    values.into_iter().map(|v| column(v, name)).collect()
+}
 
 pub use backlink::PostgresBacklinkRepository;
 pub use blob::PostgresBlobRepository;