/query-builder

name: query-builder
description: Use when the user needs to build, choose the pattern for, or optimize a SQL query against Protheus ERP tables -- covering Workarea (DbSelectArea/DbSeek) vs Embedded SQL vs TCSqlExec pattern choice, mandatory D_E_L_E_T_/xFilial filters, SIX index-aligned WHERE ordering, FWPreparedStatement parameterization to prevent SQL injection, and cross-database (PostgreSQL/MSSQL/Oracle) portability. Also triggers on Portuguese phrasing like "consulta SQL", "montar query", "otimizar consulta", "qual indice usar", "escolher entre DbSeek ou SQL", or "prevenir SQL injection no Protheus".

Protheus Query Builder

This skill helps build correct, safe, and optimized SQL against Protheus ERP tables, respecting the platform's database conventions: mandatory soft-delete (`D_E_L_E_T_`) and multi-branch (`xFilial`) filters, Hungarian-notation field names, dictionary-driven physical schemas (`RetSqlName()`), and SIX index alignment. It guides the agent to choose the right access pattern -- Workarea navigation vs Embedded SQL vs raw `TCSqlExec` -- enforce mandatory filters, order `WHERE` clauses to match available indexes, and parameterize every dynamic value with `FWPreparedStatement` to eliminate injection risk.

Activate this skill when building any query against Protheus tables (standard `SA*`/`SE*`/`SF*` or custom `Z*`), deciding between `DbSelectArea`/`DbSeek` and Embedded SQL, reviewing code for missing mandatory filters, adding parameterized queries, diagnosing slow queries via index misalignment, or writing cross-database code. It does not cover `BeginSQL`/`EndSQL` macro syntax itself (see `embedded-sql`, its companion skill for macro details), nor record locking semantics during writes (see `protheus-locks-deadlocks`).

| Reference file | Read when | |---|---| | reference.md | Always -- database conventions, table/field naming, mandatory filters, pattern-choice overview | | patterns-workarea.md | Generating record-by-record code with `DbSelectArea` + `DbSeek` + `RecLock` | | patterns-fwpreparedstatement.md | Building parameterized `TCQuery`/`TCSqlExec`, LIKE clauses, INSERT/UPDATE/DELETE | | index-awareness.md | Choosing/validating an index, ordering WHERE clauses, common SIX key expressions | | cross-database.md | Using `ChangeQuery()`, `TCGetDB()`, DBAccess macros, MSSQL/PostgreSQL/Oracle equivalents |