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Merged
magnusp merged 1 commit into from
Oct 24, 2026
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refactor(jdbc): shape getColumns rows through named records #230

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177 changes: 177 additions & 0 deletions libsql-jdbc/src/main/java/com/github/magnusp/libsql/jdbc/ColumnMetadata.java
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Original file line number Diff line number Diff line change
@@ -0,0 +1,177 @@
package com.github.magnusp.libsql.jdbc;

import com.github.magnusp.libsql.hrana.codec.Col;
import com.github.magnusp.libsql.hrana.codec.Row;
import com.github.magnusp.libsql.hrana.codec.StmtResult;
import com.github.magnusp.libsql.hrana.codec.Value;

import java.sql.DatabaseMetaData;
import java.sql.Types;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.regex.Pattern;

/**
* Shapes {@code pragma_table_xinfo} rows into the 24-column JDBC {@link DatabaseMetaData#getColumns}
* shape. The pragma select list is positional by contract; from {@link PragmaRow} onward every value
* has a name.
*/
final class ColumnMetadata {

private static final Pattern INTEGER_TYPE = Pattern.compile(".*(INT|BOOL).*");
private static final Pattern VARCHAR_TYPE = Pattern.compile(".*(CHAR|CLOB|TEXT|BLOB).*");
private static final Pattern FLOAT_TYPE = Pattern.compile(".*(REAL|FLOA|DOUB|DEC|NUM).*");
private static final int UNKNOWN_COLUMN_SIZE = 2_000_000_000;
private static final int DEFAULT_DECIMAL_DIGITS = 10;

private ColumnMetadata() {}

static StmtResult columns(StmtResult raw, List<Col> columns) {
List<Row> rows = new ArrayList<>();
if (raw != null && raw.rows() != null) {
for (Row row : raw.rows()) {
rows.add(JdbcRow.from(PragmaRow.fromRow(row)).toRow());
}
}
return new StmtResult(columns, rows, 0, null);
}

/** One {@code pragma_table_xinfo} row, in the order {@code MetadataSql.columns} selects it. */
private record PragmaRow(
String tableName,
String createSql,
long cid,
String columnName,
String declaredType,
boolean notNull,
String columnDefault,
boolean primaryKey,
long hidden) {

private static PragmaRow fromRow(Row row) {
List<Value> values = row.values();
return new PragmaRow(
text(values.get(0)),
text(values.get(1)),
integer(values.get(2)),
text(values.get(3)),
text(values.get(4)),
integer(values.get(5)) != 0,
text(values.get(6)),
integer(values.get(7)) != 0,
integer(values.get(8)));
}
}

private record JdbcRow(
String tableName,
String columnName,
ColumnShape shape,
long ordinalPosition,
boolean notNull,
String columnDefault,
boolean autoIncrement,
boolean generated) {

private static JdbcRow from(PragmaRow pragma) {
return new JdbcRow(
pragma.tableName(),
pragma.columnName(),
columnShape(pragma.declaredType()),
pragma.cid() + 1,
pragma.notNull(),
pragma.columnDefault(),
pragma.primaryKey()
&& SqlAutoIncrement.isAutoIncrementColumn(
pragma.createSql(), pragma.columnName()),
pragma.hidden() == 2 || pragma.hidden() == 3);
}

private Row toRow() {
return new Row(List.of(
Value.ofNull(), // TABLE_CAT
Value.ofNull(), // TABLE_SCHEM
Value.of(tableName),
Value.of(columnName),
Value.of(shape.jdbcType()),
Value.of(shape.typeName()),
Value.of(shape.columnSize()),
Value.of(UNKNOWN_COLUMN_SIZE), // BUFFER_LENGTH
Value.of(shape.decimalDigits()),
Value.of(10), // NUM_PREC_RADIX is 10 by JDBC, not DECIMAL_DIGITS
Value.of(notNull ? DatabaseMetaData.columnNoNulls : DatabaseMetaData.columnNullable),
Value.ofNull(), // REMARKS stays null; libSQL has no column comments
Value.of(columnDefault),
Value.of(0), // SQL_DATA_TYPE
Value.of(0), // SQL_DATETIME_SUB
Value.of(UNKNOWN_COLUMN_SIZE), // CHAR_OCTET_LENGTH
Value.of(ordinalPosition),
Value.of(notNull ? "NO" : "YES"),
Value.ofNull(), // SCOPE_CATALOG
Value.ofNull(), // SCOPE_SCHEMA
Value.ofNull(), // SCOPE_TABLE
Value.ofNull(), // SOURCE_DATA_TYPE
Value.of(autoIncrement ? "YES" : "NO"),
Value.of(generated ? "YES" : "NO")));
}
}

private record ColumnShape(int jdbcType, String typeName, int columnSize, int decimalDigits) {}

private static ColumnShape columnShape(String declaredType) {
String typeName = declaredType == null ? "TEXT" : declaredType.toUpperCase(Locale.ENGLISH);
int jdbcType;
int decimalDigits = DEFAULT_DECIMAL_DIGITS;
if (INTEGER_TYPE.matcher(typeName).find()) {
jdbcType = Types.INTEGER;
decimalDigits = 0;
} else if (VARCHAR_TYPE.matcher(typeName).find()) {
jdbcType = Types.VARCHAR;
decimalDigits = 0;
} else if (FLOAT_TYPE.matcher(typeName).find()) {
jdbcType = Types.FLOAT;
} else {
jdbcType = Types.VARCHAR;
}

int columnSize = UNKNOWN_COLUMN_SIZE;
int startOfDimension = typeName.indexOf('(');
if (startOfDimension > 0) {
int endOfDimension = typeName.indexOf(')', startOfDimension);
if (endOfDimension > 0) {
int dimensionSeparator = typeName.indexOf(',', startOfDimension);
String integerPart;
String decimalPart;
if (dimensionSeparator > 0) {
integerPart = typeName.substring(startOfDimension + 1, dimensionSeparator);
decimalPart = typeName.substring(dimensionSeparator + 1, endOfDimension);
} else {
integerPart = typeName.substring(startOfDimension + 1, endOfDimension);
decimalPart = null;
}
try {
int integerValue = Integer.parseUnsignedInt(integerPart.trim());
if (decimalPart != null) {
decimalDigits = Integer.parseUnsignedInt(decimalPart.trim());
columnSize = integerValue + decimalDigits;
} else {
decimalDigits = 0;
columnSize = integerValue;
}
} catch (NumberFormatException ignored) {
}
}
typeName = typeName.substring(0, startOfDimension).trim();
}
return new ColumnShape(jdbcType, typeName, columnSize, decimalDigits);
}

private static String text(Value value) {
return value instanceof Value.Text text ? text.value() : null;
}

private static long integer(Value value) {
return value instanceof Value.Integer integer ? integer.value() : 0L;
}
}
159 changes: 28 additions & 131 deletions libsql-jdbc/src/main/java/com/github/magnusp/libsql/jdbc/LibsqlDatabaseMetaData.java
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Original file line number Diff line number Diff line change
Expand Up @@ -23,17 +23,12 @@

public class LibsqlDatabaseMetaData implements DatabaseMetaData {

private static final Pattern INTEGER_TYPE = Pattern.compile(".*(INT|BOOL).*");
private static final Pattern VARCHAR_TYPE = Pattern.compile(".*(CHAR|CLOB|TEXT|BLOB).*");
private static final Pattern FLOAT_TYPE = Pattern.compile(".*(REAL|FLOA|DOUB|DEC|NUM).*");
private static final Pattern NAMED_PRIMARY_KEY = Pattern.compile(
"\\bCONSTRAINT\\s*(\"[^\"]+\"|`[^`]+`|\\[[^\\]]+\\]|'[^']+'|[^\\s]+)\\s*PRIMARY\\s+KEY\\b",
Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
private static final Pattern NAMED_FOREIGN_KEY = Pattern.compile(
"\\bCONSTRAINT\\s+(\"[^\"]+\"|`[^`]+`|\\[[^\\]]+\\]|'[^']+'|[^\\s]+)\\s+FOREIGN\\s+KEY\\b",
Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
private static final int UNKNOWN_COLUMN_SIZE = 2_000_000_000;
private static final int DEFAULT_DECIMAL_DIGITS = 10;

private static final List<Col> FOREIGN_KEY_COLUMNS = List.of(
new Col("PKTABLE_CAT", "TEXT"),
Expand All @@ -51,6 +46,32 @@ public class LibsqlDatabaseMetaData implements DatabaseMetaData {
new Col("PK_NAME", "TEXT"),
new Col("DEFERRABILITY", "INTEGER"));

private static final List<Col> COLUMN_COLUMNS = List.of(
new Col("TABLE_CAT", "TEXT"),
new Col("TABLE_SCHEM", "TEXT"),
new Col("TABLE_NAME", "TEXT"),
new Col("COLUMN_NAME", "TEXT"),
new Col("DATA_TYPE", "INTEGER"),
new Col("TYPE_NAME", "TEXT"),
new Col("COLUMN_SIZE", "INTEGER"),
new Col("BUFFER_LENGTH", "INTEGER"),
new Col("DECIMAL_DIGITS", "INTEGER"),
new Col("NUM_PREC_RADIX", "INTEGER"),
new Col("NULLABLE", "INTEGER"),
new Col("REMARKS", "TEXT"),
new Col("COLUMN_DEF", "TEXT"),
new Col("SQL_DATA_TYPE", "INTEGER"),
new Col("SQL_DATETIME_SUB", "INTEGER"),
new Col("CHAR_OCTET_LENGTH", "INTEGER"),
new Col("ORDINAL_POSITION", "INTEGER"),
new Col("IS_NULLABLE", "TEXT"),
new Col("SCOPE_CATALOG", "TEXT"),
new Col("SCOPE_SCHEMA", "TEXT"),
new Col("SCOPE_TABLE", "TEXT"),
new Col("SOURCE_DATA_TYPE", "INTEGER"),
new Col("IS_AUTOINCREMENT", "TEXT"),
new Col("IS_GENERATEDCOLUMN", "TEXT"));

private static final List<Col> PRIMARY_KEY_COLUMNS = List.of(
new Col("TABLE_CAT", "TEXT"),
new Col("TABLE_SCHEM", "TEXT"),
Expand Down Expand Up @@ -458,130 +479,8 @@ public ResultSet getColumns(String catalog, String schemaPattern, String tableNa
String columnPattern = columnNamePattern == null || columnNamePattern.isEmpty() ? "%" : columnNamePattern;
// getColumns synthesizes its column labels, so the raw SQL must not drive column-origin
// resolution for the result set.
return executeMetadataQuery(MetadataSql.columns(tablePattern, columnPattern), null, LibsqlDatabaseMetaData::columnsResult);
}

private static StmtResult columnsResult(StmtResult raw) {
List<Col> columns = List.of(
new Col("TABLE_CAT", "TEXT"),
new Col("TABLE_SCHEM", "TEXT"),
new Col("TABLE_NAME", "TEXT"),
new Col("COLUMN_NAME", "TEXT"),
new Col("DATA_TYPE", "INTEGER"),
new Col("TYPE_NAME", "TEXT"),
new Col("COLUMN_SIZE", "INTEGER"),
new Col("BUFFER_LENGTH", "INTEGER"),
new Col("DECIMAL_DIGITS", "INTEGER"),
new Col("NUM_PREC_RADIX", "INTEGER"),
new Col("NULLABLE", "INTEGER"),
new Col("REMARKS", "TEXT"),
new Col("COLUMN_DEF", "TEXT"),
new Col("SQL_DATA_TYPE", "INTEGER"),
new Col("SQL_DATETIME_SUB", "INTEGER"),
new Col("CHAR_OCTET_LENGTH", "INTEGER"),
new Col("ORDINAL_POSITION", "INTEGER"),
new Col("IS_NULLABLE", "TEXT"),
new Col("SCOPE_CATALOG", "TEXT"),
new Col("SCOPE_SCHEMA", "TEXT"),
new Col("SCOPE_TABLE", "TEXT"),
new Col("SOURCE_DATA_TYPE", "INTEGER"),
new Col("IS_AUTOINCREMENT", "TEXT"),
new Col("IS_GENERATEDCOLUMN", "TEXT"));
List<Row> rows = new ArrayList<>();
if (raw != null && raw.rows() != null) {
for (Row row : raw.rows()) {
List<Value> values = row.values();
String tableName = text(values.get(0));
String createSql = text(values.get(1));
long cid = integer(values.get(2));
String columnName = text(values.get(3));
String declaredType = text(values.get(4));
boolean notNull = integer(values.get(5)) != 0;
String columnDefault = text(values.get(6));
boolean primaryKey = integer(values.get(7)) != 0;
long hidden = integer(values.get(8));

ColumnShape shape = columnShape(declaredType);
boolean autoIncrement = primaryKey
&& SqlAutoIncrement.isAutoIncrementColumn(createSql, columnName);
boolean generated = hidden == 2 || hidden == 3;

rows.add(new Row(List.of(
Value.ofNull(),
Value.ofNull(),
Value.of(tableName),
Value.of(columnName),
Value.of(shape.jdbcType()),
Value.of(shape.typeName()),
Value.of(shape.columnSize()),
Value.of(UNKNOWN_COLUMN_SIZE),
Value.of(shape.decimalDigits()),
Value.of(10),
Value.of(notNull ? DatabaseMetaData.columnNoNulls : DatabaseMetaData.columnNullable),
Value.ofNull(),
Value.of(columnDefault),
Value.of(0),
Value.of(0),
Value.of(UNKNOWN_COLUMN_SIZE),
Value.of(cid + 1),
Value.of(notNull ? "NO" : "YES"),
Value.ofNull(),
Value.ofNull(),
Value.ofNull(),
Value.ofNull(),
Value.of(autoIncrement ? "YES" : "NO"),
Value.of(generated ? "YES" : "NO"))));
}
}
return new StmtResult(columns, rows, 0, null);
}

private static ColumnShape columnShape(String declaredType) {
String typeName = declaredType == null ? "TEXT" : declaredType.toUpperCase(Locale.ENGLISH);
int jdbcType;
int decimalDigits = DEFAULT_DECIMAL_DIGITS;
if (INTEGER_TYPE.matcher(typeName).find()) {
jdbcType = Types.INTEGER;
decimalDigits = 0;
} else if (VARCHAR_TYPE.matcher(typeName).find()) {
jdbcType = Types.VARCHAR;
decimalDigits = 0;
} else if (FLOAT_TYPE.matcher(typeName).find()) {
jdbcType = Types.FLOAT;
} else {
jdbcType = Types.VARCHAR;
}

int columnSize = UNKNOWN_COLUMN_SIZE;
int startOfDimension = typeName.indexOf('(');
if (startOfDimension > 0) {
int endOfDimension = typeName.indexOf(')', startOfDimension);
if (endOfDimension > 0) {
int dimensionSeparator = typeName.indexOf(',', startOfDimension);
String integerPart;
String decimalPart;
if (dimensionSeparator > 0) {
integerPart = typeName.substring(startOfDimension + 1, dimensionSeparator);
decimalPart = typeName.substring(dimensionSeparator + 1, endOfDimension);
} else {
integerPart = typeName.substring(startOfDimension + 1, endOfDimension);
decimalPart = null;
}
try {
int integerValue = Integer.parseUnsignedInt(integerPart.trim());
if (decimalPart != null) {
decimalDigits = Integer.parseUnsignedInt(decimalPart.trim());
columnSize = integerValue + decimalDigits;
} else {
decimalDigits = 0;
columnSize = integerValue;
}
} catch (NumberFormatException ignored) {
}
}
typeName = typeName.substring(0, startOfDimension).trim();
}
return new ColumnShape(jdbcType, typeName, columnSize, decimalDigits);
return executeMetadataQuery(MetadataSql.columns(tablePattern, columnPattern), null,
raw -> ColumnMetadata.columns(raw, COLUMN_COLUMNS));
}

private static String text(Value value) {
Expand Down Expand Up @@ -825,8 +724,6 @@ private Row toRow() {
}
}

private record ColumnShape(int jdbcType, String typeName, int columnSize, int decimalDigits) {}

@Override public ResultSet getPrimaryKeys(String catalog, String schema, String table) throws SQLException {
return executeMetadataQuery(MetadataSql.primaryKeys(table), null, raw -> primaryKeysResult(raw, table));
}
Expand Down
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