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korenmiklosclaude
korenmiklos
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claude
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Add M15: save table, tempfile, preserve/restore, garbage collection
- save mytable, replace table → CREATE OR REPLACE TABLE (in-memory) - save "file.csv", replace → COPY TO (disk, unchanged) - tempfile name → registers name, creates _tempfiles schema - save to tempfile → CREATE TABLE _tempfiles.name - use from tempfile → SELECT * FROM _tempfiles.name - preserve → checkpoint CTE chain position - restore → truncate chain back to checkpoint - clear drops tempfile tables and _tempfiles schema - Explicit table saves (table option) persist across clear - 616 test assertions passing Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
1 parent e4c15ef commit f7eddff

3 files changed

Lines changed: 179 additions & 7 deletions

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‎src/include/stata_do_extension.hpp‎

Lines changed: 33 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -5,6 +5,7 @@
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#include "duckdb/planner/operator_extension.hpp"
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#include "duckdb/main/client_context_state.hpp"
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#include <unordered_map>
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#include <unordered_set>
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namespace duckdb {
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@@ -56,13 +57,45 @@ struct StataDoStateInfo : public ParserExtensionInfo {
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//! Column-to-value-label mapping: column_name -> label_name
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unordered_map<string, string> column_labels;
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//! Tempfile names (registered via tempfile command)
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unordered_set<string> tempfile_names;
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//! Whether _tempfiles schema has been created
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bool tempfiles_schema_created = false;
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//! Tempfile tables created (for garbage collection on clear)
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vector<string> tempfile_tables;
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//! Preserve checkpoint: index into cte_steps (-1 = no active preserve)
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int preserve_checkpoint = -1;
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int preserve_step_counter = -1;
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void Clear() {
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cte_steps.clear();
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step_counter = 0;
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current_source.clear();
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variable_labels.clear();
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value_label_defs.clear();
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column_labels.clear();
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tempfile_names.clear();
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preserve_checkpoint = -1;
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preserve_step_counter = -1;
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}
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//! Get SQL to drop tempfile tables and schema (called on clear)
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string BuildCleanupSQL() const {
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string sql;
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for (auto &tbl : tempfile_tables) {
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sql += "DROP TABLE IF EXISTS " + tbl + "; ";
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}
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if (tempfiles_schema_created) {
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sql += "DROP SCHEMA IF EXISTS _tempfiles CASCADE; ";
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}
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return sql;
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}
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void ClearAll() {
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Clear();
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tempfile_tables.clear();
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tempfiles_schema_created = false;
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}
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};
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‎src/stata_do_extension.cpp‎

Lines changed: 75 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -30,7 +30,7 @@ static const vector<string> STATA_COMMANDS = {"use", "list", "clear"
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"tabulate", "head", "tail", "save", "append",
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"mvencode", "reshape", "do", "label", "codebook",
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"duplicates", "expand", "export", "import",
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"merge"};
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"merge", "tempfile", "preserve", "restore"};
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// Command classification for do-file execution
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// Transformation: modifies the CTE chain state
@@ -40,7 +40,7 @@ static bool IsTransformationCommand(const string &command) {
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static const vector<string> TRANSFORMATION = {"use", "clear", "do", "keep", "drop", "generate", "replace",
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"rename", "sort", "order", "egen", "collapse", "mvencode",
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"reshape", "append", "label", "duplicates", "expand", "import",
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"merge"};
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"merge", "tempfile", "preserve", "restore"};
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for (auto &cmd : TRANSFORMATION) {
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if (command == cmd) {
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return true;
@@ -518,7 +518,51 @@ static string ProcessCommand(const StataCommand &cmd, StataDoStateInfo &state) {
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}
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if (cmd.command == "clear") {
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state.Clear();
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// Generate cleanup SQL for tracked tables, then clear state
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string cleanup = state.BuildCleanupSQL();
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state.ClearAll();
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if (!cleanup.empty()) {
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// Return cleanup SQL + OK. Multiple statements separated by ;
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// will be handled by the parser
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return cleanup + "SELECT 'OK' AS status";
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}
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return "SELECT 'OK' AS status";
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}
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if (cmd.command == "tempfile") {
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// tempfile name — register a tempfile identifier and ensure schema exists
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auto names = StringUtil::Split(cmd.arguments, ' ');
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for (auto &n : names) {
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string name = Trim(n);
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if (!name.empty()) {
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state.tempfile_names.insert(name);
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}
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}
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if (!state.tempfiles_schema_created) {
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state.tempfiles_schema_created = true;
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return "CREATE SCHEMA IF NOT EXISTS _tempfiles";
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}
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return "SELECT 'OK' AS status";
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}
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if (cmd.command == "preserve") {
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if (state.preserve_checkpoint >= 0) {
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throw ParserException("'preserve' called while already preserved. Use 'restore' first.");
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}
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state.preserve_checkpoint = static_cast<int>(state.cte_steps.size());
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state.preserve_step_counter = state.step_counter;
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return "SELECT 'OK' AS status";
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}
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if (cmd.command == "restore") {
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if (state.preserve_checkpoint < 0) {
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throw ParserException("'restore' called without a prior 'preserve'.");
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}
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// Truncate CTE chain back to the checkpoint
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state.cte_steps.resize(state.preserve_checkpoint);
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state.step_counter = state.preserve_step_counter;
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state.preserve_checkpoint = -1;
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state.preserve_step_counter = -1;
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return "SELECT 'OK' AS status";
523567
}
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@@ -1488,16 +1532,40 @@ static string ProcessCommand(const StataCommand &cmd, StataDoStateInfo &state) {
14881532
}
14891533

14901534
if (cmd.command == "save") {
1491-
string filename = ExtractQuotedString(cmd.arguments);
1492-
// Detect format from extension
1493-
string lower_fn = StringUtil::Lower(filename);
1535+
string target = ExtractQuotedString(cmd.arguments);
1536+
string lower_opts = StringUtil::Lower(cmd.options);
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bool save_as_table = (lower_opts.find("table") != string::npos ||
1538+
lower_opts.find("memory") != string::npos);
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// Check if target is a registered tempfile
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bool is_tempfile = (state.tempfile_names.find(target) != state.tempfile_names.end());
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1543+
if (save_as_table || is_tempfile) {
1544+
// Save as in-memory table
1545+
string table_name;
1546+
string full_query = state.BuildQuery("SELECT * FROM " + prev);
1547+
1548+
if (is_tempfile) {
1549+
// Tempfile → _tempfiles schema (schema created by tempfile command)
1550+
table_name = "_tempfiles." + target;
1551+
state.tempfile_tables.push_back(table_name);
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return "CREATE OR REPLACE TABLE " + table_name + " AS (" + full_query + ")";
1553+
} else {
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// Explicit table save — not garbage collected
1555+
table_name = target;
1556+
return "CREATE OR REPLACE TABLE " + table_name + " AS (" + full_query + ")";
1557+
}
1558+
}
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// Save to disk file
1561+
string lower_fn = StringUtil::Lower(target);
14941562
string format_clause;
14951563
if (StringUtil::EndsWith(lower_fn, ".csv")) {
14961564
format_clause = " (FORMAT CSV, HEADER)";
14971565
} else if (StringUtil::EndsWith(lower_fn, ".parquet")) {
14981566
format_clause = " (FORMAT PARQUET)";
14991567
}
1500-
return "COPY (" + state.BuildQuery("SELECT * FROM " + prev) + ") TO '" + filename + "'" + format_clause;
1568+
return "COPY (" + state.BuildQuery("SELECT * FROM " + prev) + ") TO '" + target + "'" + format_clause;
15011569
}
15021570

15031571
if (cmd.command == "append") {

‎test/sql/stata_do.test‎

Lines changed: 71 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -940,3 +940,74 @@ list
940940

941941
statement ok
942942
clear
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944+
# ============================================================
945+
# M15: save table, tempfile, preserve/restore
946+
# ============================================================
947+
948+
# save as in-memory table
949+
statement ok
950+
use "test/data/firms.csv", clear
951+
952+
statement ok
953+
save firms_mem, replace table
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955+
# use from in-memory table
956+
statement ok
957+
use firms_mem, clear
958+
959+
query I
960+
count
961+
----
962+
5
963+
964+
# preserve/restore
965+
statement ok
966+
use "test/data/firms.csv", clear
967+
968+
statement ok
969+
preserve
970+
971+
statement ok
972+
keep if year == 2018
973+
974+
query I
975+
count
976+
----
977+
3
978+
979+
statement ok
980+
restore
981+
982+
query I
983+
count
984+
----
985+
5
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987+
# tempfile
988+
statement ok
989+
use "test/data/firms.csv", clear
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991+
statement ok
992+
keep if year == 2018
993+
994+
statement ok
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tempfile subset
996+
997+
statement ok
998+
save subset, replace
999+
1000+
# load full data and merge with tempfile
1001+
statement ok
1002+
use "test/data/firms.csv", clear
1003+
1004+
statement ok
1005+
merge m:1 id using "_tempfiles.subset", keep(match) nogen
1006+
1007+
query I
1008+
count
1009+
----
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3
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statement ok
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clear

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